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ICS Complete Reinforced Upper Gear Box Set for ICS M4 / M16 Series Airsoft AEG

ID: 29107 (GB-ICS-MA-54)
4.7 stars, based on 3 reviews


MAP ProtectedExempt From Coupons
The manufacturer of this product enforces a strict minimum advertised price (MAP) policy which excludes this product from any additional discount coupon codes. This item, however, may qualify for free shipping.

One of ICS M4 series's most distinctive feature, is it's two piece gearbox. It allows the user the ability to install a spare one in seconds to alter the power, performance and functionality of his/her M4 in seconds. Thus, here you go! An spare upper gearbox you need with all the reinforced parts you need! Offered to you by your ICS USA distributor!
Having a spare gearbox offers you an solution in the middle of your games when an internal part wears off. Due to different FPS regulations in various fields, it also allows your rifle to be changed to the correct FPS by swapping out the spring, or the entire gearbox in seconds!

Features / Applications:
  • Having an extra ICS upper gearbox is equivalent to having a spare gun in critical situations.
  • Factory direct replacement gearbox with ICS reinforced internal parts.
  • Have a spare gearbox so your gun works for indoor FPS regulations and outdoor FPS regulations.

  • Complete tune up kit includes:
    -ICS M4 Metal Upper Gearbox with screws
    -ICS Aluminum full teeth full metal piston
    -ICS Version 2 reinforced air nozzle
    -ICS MC-02 Tappet plate for ICS M4
    -ICS Version 2 Ball bearing spring guide with screw.
    -Reinforced Aluminum Piston head with ball bearing
    -Reinforced Aluminum Cylinder head.
    -Reinforced cylinder

    California residents click here for Proposition 65 warning

    3 Customer Reviews

    (Write a review)

    by Scott D. on 03/12/2014
    "Solid upper gearbox, Aluminum Piston, Aluminum cylinder head with 2 O-rings, Aluminum slotted mushroom piston head, 5 slot cylinder with slots in the rear of the cylinder itself, copper coated spring for corrosion resistance, plastic nozzle with O-ring and a Tappet plate with spring. All together this kit performs extremely well under high wear and tear FPS ranges. The only bad things i can say are the spring is a standard pitch, very stiff and is quite hard to get into the upper once assembled and deforms under stress. The Tappet plate is VERY fragile - fired the system 5 times and it cracked in half.

    Excellent air retention
    Piston and Cylinder heads are high quality with excellent air seal when lubed properly

    Tappet plate is extremely fragile
    Spring deforms under tension and is hard to get into the gearbox
    by Daniel Y. on 09/20/2008
    "insted of useing a 1 part gearbox can you somehow put this on a M4 other than ICS?
    by troy j. on 06/11/2008
    "Fantastic Kit for ICS M4's. For about the same cost as a name brand bore up kit, you get a standalone upper gearbox for quick FPS changes or field repair. You don't have to worry about whether anything is compatible with your gun, or which parts work with what. This is everything you need, all made specifically for your gun.

    I have heard others complain of breaking the head off ICS pistons. You *must* LocTite the screw that holds the piston head on, or it'll back out. Causing it to wobble, thus causing the piston to break.

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