One of the easiest ways to tell them apart is by the press stud. L1A1 has a protruding press stud and the grips are marked L1A1 with a stores number. I don't have my reference material handy to tell you the exact number. Usually they have a blackened hilt and a bright blade.

The L1A2 is very similar to the L1A1 with the protruding press stud, but the bayonet is completely unmarked and has a parkerized finish. These were used by Australiaicon.

The L1A3 has a concave recess around the press stud and the stud does not protrude past the body of the pommel. Grips are marked L1A3 with a different stores number.
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