 GA - Goncz Assault Pistol GA-9 (9 mm), GA-4 (.45 ACP) and GA- 3 (.30) Mauser has a longer barrel at 9.5 inches and a barrel shroud for looks and heatsinking.GC - Goncz Carbine GC-9 (9 mm) with walnut forearm.GCL - Goncz Carbine with Laser GCL-9 (9 mm) has the Laser as an integral part of the gun.