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Matrix Advanced 8mm M4 / M16 Version 2 Quick Change Spring Gearbox for Airsoft AEG Rifles (460-500fps) - Rear Wired

ID: 56139 (GB-MTX-Advanced)
4.4 stars, based on 13 reviews
Matrix Advanced 8mm M4 / M16 Version 2 Quick Change Spring Gearbox for Airsoft AEG Rifles (460-500fps) - Rear Wired
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  • Precision machined CNC aluminum construction
  • High strength aluminum alloy shell
  • Integrated quick-change ball bearing spring guide allows you to quickly swap springs without complete disassembly
  • 8mm metal ball bearing bushings
  • High grade low resistance wiring
  • Brass air nozzle
  • Reinforced high-strength gear set
  • 460~500 estimated FPS
Connector Type: Small Tamiya
Compatibility: For Tokyo Marui compatible M4 / M16 Series Airsoft AEG rifles
Material: Metal alloy

Manufacturer: Matrix

Modification may be required to fit certain brands or parts.

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!

13 Customer Reviews

(Write a review)

by Luke S. on 10/11/2020
"Put this Gearbox in my APS almost a year ago now and it's still running like a champ. Getting a consistent 445-450fps and so far I haven't needed to change the spring yet. I usually prefer to not use drop-ins but I wanted instant gratification without troubleshooting and I was extremely pleased with the performance.
by Caleb A. on 05/30/2020
"I recently bought this gearbox for my G&G combat machine cm16, the gearbox required no modifications to fix but it was very difficult to get the pin through the lower receiver after that everything else for perfectly.

The stock spring is actually pretty good
I got 430 fps with .25g bbs and 390 with 390fps and I imagine It would shoot about 470 fps with .20g bbs

I upgraded my motor to a high torque motor And the gearbox sounds great and works flawless so far, but I haven't had much play time on the gearbox. The gearbox feels like quality from the outside, it's substancially heavier than the stock g&g gearbox.
The wires are pretty short which is annoying but it's useable

All in all, I would recommend this for an upgrade it's easy way to get the most out of your gun. Its easy to install and performs as advertised.
by Gabriel H. on 01/24/2020
"I dropped this into my G&G M4 A1 after the old gear box broke and it worked alright, the trigger response was meh but after a few games it stopped cycling. I discovered the spring that comes with the gear box wasn't strong enough to reset the Piston all the way so the gears were just spinning free. After looking at the spring that comes with the gear box it's absolutely trash but I did have a m110 and when I put that in the box worked unbelievably. Trigger response was unbelievably snappy for a system without a mosfet and it's so smooth. If you're going to pick this gun up I suggest grabbing a better spring to go with it but if you do you won't be disappointed.

Snappy trigger response
Smooth cycle every time
Feels great and gives a nice bit of kick without needing a blowback unit
Quick change spring system makes getting that old trash spring out ez

Spring is unusable
A bit pricy

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