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MAD BULL M120 Madbull Spring



MAD BULL always deliver with high grade products. Once again they have delivered an excellent Airsoft AEG spring, not just in terms of performance but in looks, as well.If you really want to pimp out the internals of your Airsoft gun, this spring is the one for you!This MAD BULL M120 spring will deliver consistent FPS to your rifle any day.

  • MAD BULL - M120 Spring
  • Non Linear Spring
  • M120 performance

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Product Details:

  • MAD BULL - M120 Spring
  • Non Linear Spring
  • M120 performance

Why Madbull?  More durable, Calculated Non liner design.


Buying with confidence is important and knowing that we have a no quibble returns policy will hopefully put your mind at rest.

Items must be returned in original packaging! Any faults or damage must be reported as soon as the item has been opened. If we believe damage has been inflicted by yourself, we reserve the right to refuse a return and/or refund of the item and postage.

Any returned item/s returned due to a fault or incorrectly dispatched will have your postage REFUNDED. If you are returning an item due to incorrect sizing or being unwanted you will not be refunded for return postage. To receive a full refund of your item/s you must contact us within14 days of original delivery date in original packaging. 

The stated Feet Per Second listed (FPS) is based on the first unit taken into stock from our suppliers. We check this ourselves in store using SKANAR Chronometers. Subsequent units on new deliveries or new production runs may deviate from this figure substantially. If the power level of the unit is of particular importance to you, the end user, please contact us at the time of purchase and we will try our best to cater to your needs.

11.1V LiPo batteries are for use in highly tuned and modified AEGs ONLY. The use of an 11.1V LiPo, 10.8V NiMh/NiCd or higher voltages voids all warranty on all AEGs supplied by Patrol Base Ltd. This includes units where Manufacturers, suppliers, other retailers or the Airsoft media state that a unit is 11.1V LiPo ready.

Frequently asked Questions

What is your returns period?

Our returns period is 14 days from when you initally recived the item, if you no longer want the item you can return it to us with the origional packaging. However, we will be unable to refund your postage.

How long is your warranty period?

The warranty period for all items we sell is one month from the reciept of your product. We can replace your product if was recieved damaged or broken through normal use, but not if it was through user error. If the item is found not to be damaged through user error, we can refund your postage. Please contact us to discuss replacement or the fixing of your item. 

How do I arrange a return?

To arrange a return please contact us via Telephone and we will talk you through the steps required to return your items. This typically means filling in a returns form and posting it back to us. If the product is faulty, you will recive a refund for the cost of your post.

How do I get a returns form?

To recieve a returns form please contact us via Telephone and we will E-mail you a form to print out and fill in.

Who should I use to post return items?

We suggest that you use Royal Mail 2nd Class Tracked, as it allows us to tell how much you have been charged.

Can I cancel orders which have not been dispatched?

You can cancel any order that has not been dispatched. Please call our Customer Care team on 01484 644709 between 9:30am and 5:00pm

What is your returns address?

Patrol Base Limited, 
Unit 5 Dale Street Mills, 
Dale Street, 
HD3 4TG. 

How can I contact you?

You can contact our order processing department using the following options:

  • Telephone: 01484 644709
  • E-mail:
  • E-mail:


We successfully complete 99.4% of all orders within 24hrs of being placed, providing you items are in stock! Next WORKING DAY delivery gives you free tracking updates which can be sent via email or text so you are not waiting in all day. To receive full tracking details and updates please provide a correct mobile phone number to all your orders and an up to date email address! 

If your item has not been delivered within 24hrs of choosing NEXT WORKING DAY delivery please contact our store ASAP.

Frequently Asked Questions

What is the cut-off point for next working day service?

The cut-off point for next working day service is 2:45 PM, please order before this time to ensure we can process the delivery before our courrier arrives.

Is Saturday delivery available?

Yes, we do allow for a Saturday delivery, however it is costly. A standard saturday delivery can cost between anywhere between £35-£50 plus dependent on location and weight. Please contact us beforehand so we can arrange a price for you.

Which Courrier do you use?

Our main courrier is Interlink Express, however we do also use Royal mail for deliveries where postage paid is under £4, not next-day and with an order value under £20. 

Do you deliver to Northern Ireland / Scottish Highlands / Channel Islands?

Yes we do deliver to Northern Ireland, the Scottish highlands and the Channel island, however we cannot offer Next Day service to those locations and may require additional postage cost. If an additional postage cost applies to your order we will contact you via your supplied phone number or email.  

I am ordering Krylon Spray Paint, what special rules apply to the postage of these items?

When ordering Krylon it is important to note that we cannot ship fewer than 4 cans outside of the UK, and less that 2 cans to Northern Ireland, this is due to rules for transportation of pressurised containers with our courrier service. 
We also cannot ship Krylon to non-EU countries. We apologise for any inconveniences caused.

How do I track my pacrel?

If you order was sent via Next Day Service using Interlink you will recieve an E-Mail from them with tracking details and estimated delivery time. If you did not recieve this email or cannot find your tracking information please feel free to contact us.

How can I contact you?

You can contact our order processing department using the following options:

  • Telephone: 01484 644709
  • E-mail:


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Need Help? Call a specialist on 01484 644709

Monday to Saturday 9:30am to 5:30pm, but don't forget our late night Thursdays 9:00pm closing!

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