He was originally released as Zuckuss back in 1980 until some fanboys figured out androids should have alphanumeric naming standards. This guy has a C3PO protocol droid body with a bug head. Anyway, 4-LOM was a bug like alien bounty hunter released as a Proof of Purchase mail in order figure.
Regardless, this bounty hunter is 4-LOM. The other Zuckuss is next up to bat from Gentle Giant and the bounty hunter series from Empire Strikes back is complete.
This is one figure I never had as a kid. I didn't realize how cool his rifle is. Other than that, the figure is pretty plain, but still cool looking.