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£5.99
  • Made in England
  • Fits most Airsoft AEGs
  • Different strengths available


Springs are the perfect upgrade for an instant FPS boost! They fit in most standard AEGs and have a relatively simple installation process. Many rifles these days have some sort of quick-change spring system which makes your life even easier when upgrading your rifles.

The Bolster Armouries Premium AEG Spring is the best of the best when it comes to internal springs. These are the same springs used in our Bolster Armouries rifles, that's just how premium these springs are! If you want your rifle shooting like a Bolster Armouries ONYX, then the Bolster Armouries Premium AEG Spring is certainly a step in the right direction!

£5.99
  • Made in England
  • Fits most Airsoft AEGs
  • Different strengths available


Springs are the perfect upgrade for an instant FPS boost! They fit in most standard AEGs and have a relatively simple installation process. Many rifles these days have some sort of quick-change spring system which makes your life even easier when upgrading your rifles.

The Bolster Armouries Premium AEG Spring is the best of the best when it comes to internal springs. These are the same springs used in our Bolster Armouries rifles, that's just how premium these springs are! If you want your rifle shooting like a Bolster Armouries ONYX, then the Bolster Armouries Premium AEG Spring is certainly a step in the right direction!

£5.99
  • Made in England
  • Fits most Airsoft AEGs
  • Different strengths available


Springs are the perfect upgrade for an instant FPS boost! They fit in most standard AEGs and have a relatively simple installation process. Many rifles these days have some sort of quick-change spring system which makes your life even easier when upgrading your rifles.

The Bolster Armouries Premium AEG Spring is the best of the best when it comes to internal springs. These are the same springs used in our Bolster Armouries rifles, that's just how premium these springs are! If you want your rifle shooting like a Bolster Armouries ONYX, then the Bolster Armouries Premium AEG Spring is certainly a step in the right direction!

£29.99
  • Complete V2 Gearbox
  • Fits most M4/AR-15 AEGs
  • SHS Piston & reinforced tappet plate

If your M4 needs a revamp, a new gearbox is the easiest way to do it. The Delta Armory Complete Version 2 Gearbox for M4/AR-15 AEG is compatible with almost every M4/AR-15 AEG on the market and is well-equipped with reinforced parts straight out of the gate.

This is the same gearbox used in the Delta Armory CHARLIE™ line AEGs, boasting a quick change spring guide, 18:1 steel gears running on 8mm bushings, an SHS piston with a full steel tooth rack, an SHS reinforced tappet plate and a reinforced gearbox shell with radiused cylinder window corners.

The pre-installed spring will provide around 380 FPS when installed, so if you plan to use this gearbox for anything other than a semi-auto-locked DMR build you will need an M100, M105 or weaker spring to keep it within site limits. Thankfully, the quick change spring system makes spring swaps a breeze! Whether you are breathing new life into an old M4 AEG or you are building an AEG from scratch, this complete gearbox will save you loads of time and messing around!

£4.99
  • Rubber construction
  • Replaces the HOP-up unit spring
  • Provides superb air seal

If you're the techy type and want to maximise your AEG's efficiency, the Bolster Armouries HOP-up to Barrel O-Ring Shim Set belongs in your toolbox! This set includes 10 o-rings designed to fit around the HOP-up unit and inner barrel, forcing it back to meet the gearbox as seamlessly as possible to promote maximum efficiency and reduce shot-to-shot FPS deviation.

This set is designed to replace the "one size fits all" HOP-up unit spring, providing a user-customisable solution to account for manufacturing tolerances. While this will take a bit of trial and error to get the perfect fit for your AEG it should prevent airseal qualities from reducing over time and avoid that annoying realisation that you forgot to reinstall the HOP-up spring after upgrading or maintenance!

The Bolster Armouries HOP-up to Barrel O-Ring Shim set should fit almost every AEG on the market and you probably won't need to use the full set, meaning you might even be able to replace two HOP-up springs with a single set.

£15.99
  • CNC Steel construction
  • 18:1, 16:1 and 14:1 options
  • Great V2 or V3 internal upgrade

Are you looking to increase your AEG's performance? These gears are a great place to start! The Specna Arms Steel CNC gears are reinforced and extra durable, so your rifle's internals will keep going for longer. They are compatible with both V2 and V3 gearboxes, such as standard M4s and AKs.

You have the choice of standard 18:1, which is the common gear ratio found in rifles, but these ones are built to last. 16:1 ratio, which is speedier, similar to the gears found in a CYMA Platinum, they will increase the RPS to around 25. Then you have the 14:1 ratio; these frightfully fast gears will increase your rounds per second to a ridiculously high number. Experiment at your own risk!

If you need some more reliable gears and want to upgrade your rifles' RPS at the same time, these gears are a great choice! Just make sure you know exactly what you're doing when installing and that your rifle can take a faster gearset.

£29.99
  • 6.02mm Tightbore
  • Stainless steel construction
  • Improve accuracy and FPS

If you are looking for accuracy and FPS upgrades, a tightbore inner barrel is the easiest way to get a bit more from your current setup without adding strain to the gearbox. With this stainless steel tightbore from ZCI installed, you should see a slight FPS increase due to improved air seal, and better accuracy down range thanks to the tighter bore and precise internal finish.

This inner barrel is compatible with standard AEG HOP-up units and is 430mm in length, making it well-suited to 17-inch outer-barrelled AEGs. Its stainless steel construction adds significant rigidity when compared with brass barrels, meaning no amount of rapid fire can cause this barrel to flex, and its finely polished internal surface should guide your BBs onto target with minimal interruption to its flight path.

£239.99
  • Complete drop-in HPA engine
  • Programmable FCU Included
  • For Version 2 gearboxes

If you've decided to join the dark side and HPA your M4, this set will sort you out! The Storm Airsoft HP-R Storm System HPA Engine is a complete drop-in conversion kit for rear-wired version 2 gearboxes, packaged with everything you need to convert your AEG, bar the usual HPA regulator, airline and hose.

The included FCU offers a wide range of adjustable parameters, including programmable fire modes, rate of fire adjustment, and nozzle dwell time adjustment, ensuring reliable feeding with every shot. While it is a drop-in kit, this set will require a certain amount of familiarity with AEG internals and HPA. Luckily, Storm Airsoft provides a useful installation video which makes the process even easier.

Benefits of running HPA over a standard AEG gearbox include minimal FPS deviation between shots for improved accuracy, near-instantaneous trigger response for cranking out those double taps and a wide range of tuning options and adjustments, perfect for casual skirmishers looking to take their build to the next level. If you want the competitive edge HPA provides with minimal effort, the Storm Airsoft HP-R Storm System HPA Engine is the way to go!

£9.99
  • Steel construction
  • Standard ratio gearset
  • For Version 2 & 3 gearboxes

If you're old AEG's internals are beaten, battered or bruised, Specna Arms 18:1 Replacement Steel Gear Set for V2/3 Gearboxes might be the fix you need! This standard ratio gearset is made from steel and compatible with any version 2 or version 3 gearbox-equipped AEG. Being a standard 18:1 ratio set, these gears will turn once for every 18 motor revolutions, giving you a great balance between speed and torque.

These are the perfect replacement parts to keep around just in case of the worst, or you finally get the time to bring that antique airsoft platform back to life.

£14.99
  • Polymer construction
  • Compatible with most M4 AEGs
  • Specna Core™ original replacement part

If you need a replacement lower receiver for your M4/AR-15 AEG, this is perfect for you! This Specna Arms Lower Receiver is an original replacement part for the Specna Arms CORE™ series, but is compatible with most M4/AR-15 AEGS, thanks to its standard shape and dimensions.

It is constructed from polymer, features a preinstalled fire selector, as well as some cool-looking Specna Arms trademarks. This is a great replacement part to get your old Airsoft platforms back up and running. It's affordable and lightweight, making it a perfect part for your loaner/beginner replica!

£7.99
  • Ideal replacement part
  • For V2 and V3 gearboxes
  • Polymer construction

If you need a quick, cheap replacement piston head for your Assault rifle, you've come to the right place. The Specna Arms Replacement Piston Head for V2/3 Gearboxes is identical to the piston head that comes in CORE series platforms. This means that, whilst it's nothing special, it is reliable and good enough to be installed in a stock platform. It is the perfect spare part to have around for your V2 and V3 gearboxes.

£29.99
  • V2 style geabox shell
  • 8mm Bushings included
  • For Enter & Convert™ Or SAEC™ platforms

If your old Specna Arms platform is struggling internally, check the gearbox! It may be damaged, and if so, you need this! The Specna Arms V2 gearbox is specifically for platforms with the Enter & Convert™ or SAEC™ quick change systems, which are found in most of their platforms.

It includes the gearbox bearings and also includes the quick-change spring bearings, which are useful as they can be hard to otherwise source. This is a V2 gearbox, but it is unlikely to be compatible if your platform does not have either of those quick-change spring systems created by Specna Arms.

£84.99
  • Steel construction
  • For ARCTURUS AK12
  • Original replacement part

If your ARCTURUS AK12 has a damaged receiver, this is the perfect replacement! It is constructed from steel, meaning it is very durable and realistic feeling. It has detailed mock rivets and realistic stamped receiver markings, which are perfect for those who like keeping their kit as true to life as possible.

This replacement receiver is compatible with the ARCTURUS AT-AK12; it is unclear whether it is compatible with other brands or versions of the AK platform. If you need a new replacement part for your favourite ARCTURUS AK, the ARCTURUS AT-AK12 Full Steel Receiver should be exactly what you want!

£8.99
  • Progressive Coiling
  • Coloured Rating Tip
  • SiCr Zinc Coated Steel

Produced to an incredibly high quality with the best mil-spec steel rated SiCr. Every spring no matter the rating has gone through a full quality control test by ASG for your peace of mind that you are fitting a reliable spring.

£11.99
  • Soft Bucking
  • Grippy Material
  • Air-Tight Design

A soft Hop Rubber for Marui compatible AEGs offering an air-tight design, which comes supplied with a nub and is a purple colour.

£36.99
  • Stainless Steel
  • 6.03mm Tight Bore
  • Increased Performance

An upgrade Airsoft 6mm BB Gun inner Barrel which is compatible with Airsoft AEG Barrel Compatible Hop-Up units.

£41.49
  • Stainless Steel
  • 6.03mm Tight Bore
  • Increased Performance

An upgrade Airsoft 6mm BB Gun inner Barrel which is compatible with Airsoft AEG Barrel Compatible Hop-Up units.

£43.99
  • Stainless Steel
  • 6.03mm Tight Bore
  • Increased Performance

An upgrade Airsoft 6mm BB Gun inner Barrel which is compatible with Airsoft AEG Barrel Compatible Hop-Up units.

£44.99
  • Stainless Steel
  • 6.03mm Tight Bore
  • Increased Performance

An upgrade Airsoft 6mm BB Gun inner Barrel which is compatible with Airsoft AEG Barrel Compatible Hop-Up units.

£45.49
  • Stainless Steel
  • 6.03mm Tight Bore
  • Increased Performance

An upgrade Airsoft 6mm BB Gun inner Barrel which is compatible with Airsoft AEG Barrel Compatible Hop-Up units.

£45.99
  • Stainless Steel
  • 6.03mm Tight Bore
  • Increased Performance

An upgrade Airsoft 6mm BB Gun inner Barrel which is compatible with Airsoft AEG Barrel Compatible Hop-Up units.

£16.99
  • 6.02mm Precision barrel
  • Stainless steel construction
  • AEG Barrel cut - Fits most Airsoft AEGs

If you want to improve your AEGs accuracy, range and consistency, a barrel upgrade is a great start! The Specna Arms 6.02mm Steel Tightbore Inner Barrel promises to be an improvement even over stock 6.03mm brass tightbore barrels and its stainless steel construction makes it far more rigid and less prone to bends than other brass and aluminium barrels.

This barrel is cut for standard Airsoft AEGs and should fit most of them, though we suggest referring to the product description of your gun to find out what length you need. The standard AEG barrel cuts mean you can use this precision barrel with standard AEG HOP-up buckings, HOP-up nubs and HOP-up units, meaning all your existing parts should fit and plenty of opportunities to pair this barrel with other accuracy upgrades. If accuracy is a priority for you this upgraded barrel is a must!

£17.99
  • 6.02mm Precision barrel
  • Stainless steel construction
  • AEG Barrel cut - Fits most Airsoft AEGs

If you want to improve your AEGs accuracy, range and consistency, a barrel upgrade is a great start! The Specna Arms 6.02mm Steel Tightbore Inner Barrel promises to be an improvement even over stock 6.03mm brass tightbore barrels and its stainless steel construction makes it far more rigid and less prone to bends than other brass and aluminium barrels.

This barrel is cut for standard Airsoft AEGs and should fit most of them, though we suggest referring to the product description of your gun to find out what length you need. The standard AEG barrel cuts mean you can use this precision barrel with standard AEG HOP-up buckings, HOP-up nubs and HOP-up units, meaning all your existing parts should fit and plenty of opportunities to pair this barrel with other accuracy upgrades. If accuracy is a priority for you this upgraded barrel is a must!

£18.99
  • 6.02mm Precision barrel
  • Stainless steel construction
  • AEG Barrel cut - Fits most Airsoft AEGs

If you want to improve your AEGs accuracy, range and consistency, a barrel upgrade is a great start! The Specna Arms 6.02mm Steel Tightbore Inner Barrel promises to be an improvement even over stock 6.03mm brass tightbore barrels and its stainless steel construction makes it far more rigid and less prone to bends than other brass and aluminium barrels.

This barrel is cut for standard Airsoft AEGs and should fit most of them, though we suggest referring to the product description of your gun to find out what length you need. The standard AEG barrel cuts mean you can use this precision barrel with standard AEG HOP-up buckings, HOP-up nubs and HOP-up units, meaning all your existing parts should fit and plenty of opportunities to pair this barrel with other accuracy upgrades. If accuracy is a priority for you this upgraded barrel is a must!

£19.99
  • 6.02mm Precision barrel
  • Stainless steel construction
  • AEG Barrel cut - Fits most Airsoft AEGs

If you want to improve your AEGs accuracy, range and consistency, a barrel upgrade is a great start! The Specna Arms 6.02mm Steel Tightbore Inner Barrel promises to be an improvement even over stock 6.03mm brass tightbore barrels and its stainless steel construction makes it far more rigid and less prone to bends than other brass and aluminium barrels.

This barrel is cut for standard Airsoft AEGs and should fit most of them, though we suggest referring to the product description of your gun to find out what length you need. The standard AEG barrel cuts mean you can use this precision barrel with standard AEG HOP-up buckings, HOP-up nubs and HOP-up units, meaning all your existing parts should fit and plenty of opportunities to pair this barrel with other accuracy upgrades. If accuracy is a priority for you this upgraded barrel is a must!

£21.99
  • 6.02mm Precision barrel
  • Stainless steel construction
  • AEG Barrel cut - Fits most Airsoft AEGs

If you want to improve your AEGs accuracy, range and consistency, a barrel upgrade is a great start! The Specna Arms 6.02mm Steel Tightbore Inner Barrel promises to be an improvement even over stock 6.03mm brass tightbore barrels and its stainless steel construction makes it far more rigid and less prone to bends than other brass and aluminium barrels.

This barrel is cut for standard Airsoft AEGs and should fit most of them, though we suggest referring to the product description of your gun to find out what length you need. The standard AEG barrel cuts mean you can use this precision barrel with standard AEG HOP-up buckings, HOP-up nubs and HOP-up units, meaning all your existing parts should fit and plenty of opportunities to pair this barrel with other accuracy upgrades. If accuracy is a priority for you this upgraded barrel is a must!

£25.99
  • 6.02mm Precision barrel
  • Stainless steel construction
  • AEG Barrel cut - Fits most Airsoft AEGs

If you want to improve your AEGs accuracy, range and consistency, a barrel upgrade is a great start! The Specna Arms 6.02mm Steel Tightbore Inner Barrel promises to be an improvement even over stock 6.03mm brass tightbore barrels and its stainless steel construction makes it far more rigid and less prone to bends than other brass and aluminium barrels.

This barrel is cut for standard Airsoft AEGs and should fit most of them, though we suggest referring to the product description of your gun to find out what length you need. The standard AEG barrel cuts mean you can use this precision barrel with standard AEG HOP-up buckings, HOP-up nubs and HOP-up units, meaning all your existing parts should fit and plenty of opportunities to pair this barrel with other accuracy upgrades. If accuracy is a priority for you this upgraded barrel is a must!

£31.99
  • 6.02mm Precision barrel
  • Stainless steel construction
  • AEG Barrel cut - Fits most Airsoft AEGs

If you want to improve your AEGs accuracy, range and consistency, a barrel upgrade is a great start! The Specna Arms 6.02mm Steel Tightbore Inner Barrel promises to be an improvement even over stock 6.03mm brass tightbore barrels and its stainless steel construction makes it far more rigid and less prone to bends than other brass and aluminium barrels.

This barrel is cut for standard Airsoft AEGs and should fit most of them, though we suggest referring to the product description of your gun to find out what length you need. The standard AEG barrel cuts mean you can use this precision barrel with standard AEG HOP-up buckings, HOP-up nubs and HOP-up units, meaning all your existing parts should fit and plenty of opportunities to pair this barrel with other accuracy upgrades. If accuracy is a priority for you this upgraded barrel is a must!

£14.99
  • R-HOP Kit for AEGs
  • Includes bucking & nub
  • Extend range & improve accuracy

Whether you're building a DMR or simply want more range from your standard AEG, an R-HOP kit can make all the difference. Unlike other R-HOP kits on the market, the Trusight Tru-Hop Gen.3 is designed to be effectively a drop-in installation, with no need for adding patches of various sizes and includes both the HOP-up bucking and a concave HOP-up nub.

The set is designed to be widely compatible and should fit most Airsoft AEG spec inner barrels, though due to its enlarged contact patch, it will only work with inner barrels with a window measuring approximately 5mm in length x 1.7mm in depth. If you are happy to get stuck in with your AEG internals and you're looking for range and accuracy improvements, the Trusight Tru-Hop Gen.3 Hop-Up Rubber is what you need!

£8.99
  • R-HOP Kit - Improves accuracy
  • Includes bucking, HOP arm & nub
  • Ideal for any accurised AEG build

If you're looking for accuracy improvements for your M4/AR-15 AEG, the Delta Armory TRINITY R-Hop Bucking Bundle for AEG is what you need to tighten your groupings. This set includes an enhanced HOP-up arm, HOP-up bucking and OMEGA-style nub manufactured for Delta by upgrade legends Psionic Upgrades. The included HOP-up arm is designed for M4/AR-15 AEG rotary HOP-up units, specifically the Delta Armory/Specna Arms/Evolution/Lancer Tactical type but the bucking and nub are compatible with other Airsoft AEGs of all different shapes and sizes.

The inner patch of the TRINITY bucking is diamond-shaped, similar to the Maple Leaf Super bucking, intended to improve accuracy by applying backspin more consistently. The advantage of using a TRINITY set rather than doing all the mods yourself is its simple drop-in installation, low price compared to sourcing a separate bucking, nub and HOP-up arm and guaranteed compatibility, meaning no chance your nub doesn't work with your chosen bucking. If you're looking for tighter groupings from your Airsoft AEG, the TRINITY R-HOP Bucking Bundle is the one to go for!

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