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Matrix 5KU Steel CNC Hopup Air Seal Chamber for Western Arms King Arms Airsoft M4 GBB Series

ID: 29519 (HU-MTX-RAWA)
4.0 stars, based on 2 reviews
Matrix 5KU Steel CNC Hopup Air Seal Chamber for Western Arms King Arms Airsoft M4 GBB Series
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Matrix5KU / APS


Matrix 5KU Steel Hopup Air Seal Chamber for Western Arms Airsoft M4 GBB Series
*Works for G&P, King Arms, A&K and other compatible M4 GBB rifles.

This new release will enable your Western Arms M4 blowback to be powered with standard gas here in the USA. Due to the regulations in Japan, Western Arms M4 blowback series are equipped with only a ABS hopup unit for the weak 134A gas they are only allowed to use in Japan. This hopup unit is a must have for all Western Arms blowback M4 owners. It will stabilize your air seal chamber and its a hundred times more durable and reinforced than the original hopup chamber with even better air seal.
For experienced users recommended, consult an certified technician for assistance if necessary.

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!

About 5KU / APS

5KU is a division of APS Limited, focused on manufacturing high quality aluminum and steel external upgrade accessories for AEG and GBB airsoft guns.

2 Customer Reviews

(Write a review)

by Bin Q. on 07/11/2008
"Finally! Problem solved! For those that are planning on using 134A gas for your western arms M4 blowback....i don't think you can find the gas and it shoots better with green gas anyways
by Nash G. on 08/08/2017

Now for the actual review, Overall build quality is very high, It IS indeed made on a Mill and lathe and the design is much better than the standard unit. However! They should write in the description that this is not a complete hop-up unit. It is only an upgraded housing for the components.

Build Quality is 5 out of 5
Description of product is 1 out of 5.

The bottom line is however, I would purchase it again.

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