Next up on the M4A1 MWS GBB series from Tokyo Marui is the M4A1 Carbine MWS GBB . Slated to be released on the 7th of September 2017, this uses the Zet System which is highly durable and can provide high performance. This version also is the traditional M4A1 carbine with the handguard with no rail attachement and a carry handle that can be removed revealing a flat top rail on the receiver to mount accessories.