This reinforced Spring Guide replace the original Spring Guide of AEG Gear Box.
This spring guide with Ball Bearing is designed to minimize the load for the motor caused by the spring tension.
Especially important for upgraded AEG to install this.
Backstop is specially equipped with Ball Bearing to prevent Spring Tension build-up during Full Auto Shooting Mode. It greatly reduces the risk of spring breakage.
Suitable for Tokyo Marui System Ver 2 Gear Box.
NOT suitable for APS, Systema and other brand's ver 2 box with Quick Spring change function.