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Matrix / AIM Lipoly Ready 8mm Complete Gearbox for M4 / M16 series Airsoft AEG ( M120 / Back Wiring)

ID: 30248 (GB-Monster-120B)
4.6 stars, based on 21 reviews
Matrix / AIM Lipoly Ready 8mm Complete Gearbox for M4 / M16 series Airsoft AEG ( M120 / Back Wiring)
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Matrix / AIM Lipoly Ready 8mm Complete Gearbox Set for M4 / M16 series Airsoft AEG (Monster Torque) - Wiring to the Back / Stock

*Motor Not Included / Sold Separately. Recommended Matrix Magnum Motor.

For Experienced players only. This complete gearbox set is essentially a pre-assembled complete reinforced / tune up kit for your M4 / M16 series AEG. Manufactured by Matrix Tactical Systems, one of the most established, reliable and well known Airsoft manufacture in the world. This gearbox is an affordable alternative over the Systema gearbox with 8mm bearing sets. The Mecha box shell is modeled after Systema's new gearbox design with thickened shell. With the more stabilized 8mm bearing set, this gearbox is more attractive than ever!

Manufacture: Matrix Tactical Systems. OEM: AIM. Matrix is the exclusive US Distributor for AIM Products.
Compatibility: Tokyo Marui, Classic Army, Echo1, JG, G&G, G&P, Echo1, DBOY, SRC, A&K, KWA and compatible models. Modification might be required for certain brands.
Matrix Tactical Systems Gearbox Models : Available in Monster Torque and Tornado High speed. Front wire and rear wire.

- Systema / G&P / Classic Army Type 8mm Enhanced "Thick Type" Mecha Box Shell.
- M120 Spring. Velocity out put for this gearbox is around 400~440 FPS.
- Low Resistance / High Capacity / High conductivity / Wire & switch assembly Set.
- High Grade 8mm Metal Bearing Set Installed. Providing enhanced stability over the 6mm and 7mm gearboxes
- Ball bearing CNC Stainless metal spring guide.
- Matrix Ultra High Performance High Speed Piston with Metal full teeth strip.
- CNC Stainless Steel Cylinder Head.
- Reinforced Silent Polycarbonate Piston Head.
- Steel Gear Set
- Reinforced Nylon Smooth Selector plate and tappet plate.
- Reinforced Ball Bearing Polycarbonate Piston Head.
- Reinforced Matrix Monster (Torque Up) Gear set Installed.

Complete Gearbox Disclaimer:
We have compiled a series of videos for AEG take down, assembly and gearbox for your reference. Recommended for experienced players only. A "gearbox" virtually never breaks, offers spare parts for all components. All gearboxes are sold as complete set of parts and "AS IS". All the gearbox are directly from manufacture. Buyer responsible for fine tuning and proper installation. is not responsible for shimming it perfectly or playing the game of airsoft for you.
For more information on complete gearboxes, please visit: Complete AEG Gearbox

A good gearbox on par with the KWA M4 gearbox. One advantage of this gearbox over the KWA is that all 6 bearings are standard size 8mm bearings you can buy. Making it much easier to work on. The monster gear set can power up to M170 spring combined with magnum motor. The inner wall of the gearbox is reinforced, just like the Systema new type Mecha box shell, with all the inner walls thickened. Easy installation for most major brands of M4 / M16 series AEG. Great performance.
To install this gearbox on a MOD5 series, although it is a version 2, the nozzle, selector plate and trigger are not the same. Slight work and gearbox knowledge will be required.

California residents click here for Proposition 65 warning

21 Customer Reviews

(Write a review)

by Kevin S. on 05/22/2016
"This gearbox works great until the single shot safety lock breaks off. This has happened in 2 of the same gearboxes. I would recommend a G&P over this gearbox all day long.
by Nicholas E. on 02/17/2015
"Very nice gearbox. I got it to drop into my old Dboys and it's done it's job beautifully.

Pros- good fps, rather quiet, fits well, solidly built, and durable.

Cons- Semi-auto function is a little screwy, I have burst fire and full auto now. Wiring is extremely short.

I would absolutely recommend this and a bag of .25s to maximize the range of it.
by alex j. on 05/03/2014
"I bought this gearbox just under two years ago and it has served me well up to this point. I'll start with the good things about it. All of the internals are very strong and well made, however I have had to replace the spur gear due to a tooth fracturing off of it. While the internals are very good that doesn't matter at all if the gearbox shell isn't built well, which it is not. One week ago the front end of both halves of the shell fractured right off where this piston hits the cylinder head. This is a horrible gearbox in terms of longevity but when it works it works well, This gearbox has been run completely stock except for a change of gears due to the tooth fracture, I put in JG standard gears as a replacement. I do not go airsofting every weekend so this gearbox did not see extensive use, I usually go every 6 weeks or so. This break will render your gun useless and will cause stress on the hop up if you do not find the fracture in time. This may also cause your hop up to break leading to many headaches as I have experienced.

Would I recommend this? NO-NOT EVER, Unless you plan on only going airsofting once. I am being dead serious-DO NOT BUY THIS.

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