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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.

About Matrix

Established in 2001 for Airsofters by Airsofters. Team Matrix thrive on the vision to better the sport of Airsoft with affordable high quality Airsoft equipment. With decades of experiences as Airsoft enthusiasts ourselves, we live, sleep, and breathe Airsoft. Matrix offers a wide selection of skirmish grade replicas from rifles to pistols, a wide variety of accessories, and tactical equipment from helmets to boots. It is the Matrix mission to prepare every Airsoft shooter the perfect experience!

21 Customer Reviews

(Write a review)

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 Sean D. on 12/09/2012

Absolutely wonderful. I bought this with the Matrix Magnum 3000 motor, performs like a dream.

First thing I did with it was void the warranty by opening it up. Inside, lots of nice parts. The spring guide stainless steel, as is the cylinder head. Unfortunately, the selector plate did not have contacts, and the wiring set didn't have them for the selector plate either. Wah. Didn't matter, cuz I bought a MOSFET system with a trigger set included, and I had a spare selector plate with trigger contacts. Works very well.

Has what the picture says inside.
Great performance.
Pre-shimmed gears. If you open it up, make sure they don't go flying off so you know where each shim was.
Powerful, well worth the price.

Wiring is extremely short, not even an inch out of the gearbox. If you try to fit it in your lower reciever, the tamiya connecter will probably rip off. It did for me.
No trigger contacts on the selector switch or corresponding ones on the trigger set.

Overall, a very nice gearbox, with a 363mm MadBull V2 6.03mm, madbull ultimate hopup, MOSFET, and this gearbox well outperforming a KWA SR10 without upgrades.
by Mathew U. on 12/19/2011
"I got this in the mail today and started building my AEG from scratch(almost).I'm really glad I got this pre-assembled gearbox, a little greasing and my gun was shooting amazing. Saved a lot of time. Only con is the wiring in the back was too short - would have rather seen regular wire crimps instead of a small male tamiya connector. After ripping that off all was good. Great product.

Suggest that you buy it with some extra wiring.

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