This Ruger manufactured late variation barrel band screw with out the slight concave to the straight slot head is for the later model 44 semi-auto carbine and is in very good condition with light wear. (file photo)
Note: Ruger model 44 semi-auto carbines with the following serial numbs have been observed with this late variation barrel band screw:
100 Prefix: 100-13353 & 100-36694
102 Prefix: 102-06552, 102-23818, 102-51716 & 102-67115