The KJ Works M4 Gas Blowback Rifle gets a two-tone look. Cesar and Javier of 0'20 Magazine show us the new KJ Works M4 Gas Blowback Rifle that comes with a new handguard as well as folding sights. We assume this the 3rd version of the M4 GBB system that was designed by Tanio Koba as evidenced in the use the magazine that is design to minimise the cool down effect.