This Checkmate is missing a barrel and an M16 frame. Please see photos. I don't know exactly what barrels are compatible. The marker is new but somewhere in the years of sitting in a box the feedneck was dinged. Please see photos. This will need the barrel, frame and a complete rebuild. I also don't know if internal pieces are complete, there could also be damage internally. I received a box of these long long ago and never did anything with them.