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G&P Complete 400 FPS 8mm Reinforced gear box for M4 M16 Airsoft AEG - Standard Deans / Front Wiring

ID: 39749 (GB-GP-EV-GB003F)
4.7 stars, based on 3 reviews
G&P Complete 400 FPS 8mm Reinforced gear box for M4 M16 Airsoft AEG - Standard Deans / Front Wiring
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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.
G&P Complete 400 FPS 8mm Reinforced gear box for M4 M16 Airsoft AEG - Standard Deans / Front Wiring

Looking to upgrade your rifle into one that performs like a G&P? G&P Rifles feature this custom made gearbox, exclusive to, and hand-built individually by the top technicians in Hong Kong. G&P rifles shoot better than the competition due to their superior parts. This is a great gearbox to have as a primary, spare, to repair, replace or upgrade. Recommended for advanced players who have a grasp on gearbox installation, tuning and possible modification due to variations with brands of M4 rifles on the market.

Power: 400+ FPS. Can be upgraded to use higher power spring.
Weight: 740g
Wiring Location: Front Wired
Plug type: Standard Deans Plug
Type: Version II / 8mm bearing / For M4, M16 and other compatible models

Manufacturer: G&P

-8mm Reinforced Bearing Gearbox Shell
-8mm Steel Bearings
-8mm Selector Plate
-Reinforced Cylinder
-Reinforced Metal Cylinder Head
-Reinforced Metal Nozzle
-Reinforced Metal Spring Guide
-Reinforced Piston Head
-Reinforced Piston
-Reinforced Steel Gears
-Reinforced Tappet
-Reinforced High Flux Electronic wire & switch

(All the parts are G&P factory direct reinforced parts)

*Fine Tuning May be required for best performance. Upgraded gear boxes are recommended for advanced players and may require tuning.

*Motor in image not included.

Complete Gearbox Disclaimer: (Recommended for advanced users)
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

About G&P

Established in 1995, G&P is among the oldest Military-simulation and training Airsoft manufacturers in the world. Started as a top combat light provider for law enforcement and military agencies around the world, G&P branched into Airsoft manufacturing with the same belief to never sacrifice quality for lower price. Their motto is visible on every G&P product. Every G&P AEG rifle is hand assembled and individually fine-tuned by top technicians in the industry to match G&P's unparalleled quality and reputation. G&P utilizes CNC precision machining and real-steel finish/coating processes on many of their products.

3 Customer Reviews

(Write a review)

by dan w. on 04/19/2015
"i bought 2 black ops vipers for christmas in 2013, one of them finally had trigger issues so i decided to upgrade the guts. this gearbox dropped right in, requiring only slight modification to the ORIGINAL motor connectors (i didn't buy a motor), the original 8.4v/800ma battery wouldn't turn the motor, but i had a 8.4/1600ma battery that i use for another gun and it works amazingly well. the diference is clearly visible with the naked eye, over 400FPS with .20 gram bbs. i lost the cool blow back and charging bolt effects of the viper, but it's well worth the 85 dollars i paid. it's really all metal bearings, super nice, well over 5000 rounds later and it's super awesome, extremely high rate of fire compared to the stock viper gearbox in my other gun. the only con i have is that occasionally the selector switch goofs up when going from semi to full out, and it locks you out like it is on "safe". but switching back and forth again fixes it. overall A+
by Juliet C. on 05/04/2014
"I love this gearbox I am running a 11.4v lipo in this with the matrix magnum motor and i can get a good 21 rounds per second

pros: great drop in gearbox

cons: in the picture it shows a mosfet but it does not come with one
by Garett P. on 03/17/2014
"Amazing I m buying a second one it is perfect for just a drop in into any m4

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