TAF Custom show us their customised GHK Gas Blowback Rifle. This custom gas blowback rifle is equipped with Maple Leaf Precision's 2022 new product "Hummingbird" short stroke bolt assembly which can be ordered from Ruten. This is maintenance-free straight up, can be directly replaced with GHK original GBB bolts. It can increase the rate of fire up to about 18 rounds per second. The traditional M4 can be removed from the support rod structure and become a no-support or foldable support design, which increases the convenience of use. The bolt can be fixed in the back without bullet, it will not affect the original GBB operation habit. It is compatible with old and new GHK M4 GBB.