Telling   the Optimus Prime  gas nozzle apart . G1 OP gas Nozzle Type 1 Fred's Workshop has identified 2 versions of the G1 Type 2 The main thing to lean is how to tell a G1 Type 2 for a G2 (called a Type 4 by Fred) because it also concerns proper fit to hose. G2 hose has a larger diameter than the G1. G1 Type 2 G2 Type 2 The one thing that stand's out the most between the Typ2 G1 and G2 is the thinner trigger guard in the G1. There is a lot more "airspace" in the area between the trigger and guard in the G1 In the next three photos the G1 Type 2 is on top. This last course you can take is to keep a G1 hose always on hand to test fit. That's how I double check.