Re: IBM Corp M1 Carbine .30 caliber Rifle
IBM made some 346,500 M1 carbines in WWII. That one has had all the upgrades, including the safety (take a better look, Gabob). There were not two models of the M1 Carbine, but early carbines were upgraded with modified parts as time went on. (The M2 carbine is selective fire and is classed as a machinegun.) Early carbines are more valuable, but ones that escaped upgrades are uncommon.