This is an amazing reinforced gearbox of "ZAMAK" alloy was installed in the Tokio Marui G3A3 with other Modify part's. (Piston and cylinder head, cylinder, M120 Modify spring and other...)
That gearbox have special reinforced elements in the front.
They are outside and inside of gearbox.
To post a reinforced elemnts in gearbox, in the tappet-plate made a special slot for sliding on the elements of the gain.
With Modify M120 spring, speed of 0.2g BB was more than 440 FPS!
Were shot more than 25 thousand of BB's, than gearbox was opened.
We was not found any signs of wear or part's break.
The quality of this product the best of what is currently available for its price.
We used the Firefox Lithium-Polymer battery (11.1V 2200mAh)
Deep Fire 6.04 500mm precision barrel
Prometheus Blue Hop-up rubber
Tokio Marui EG 700 motor