Bayonet lugs were not fitted on the original M1 - though they were added in 1945 (apparently the occupation troops in Germany were the first to receive Carbines which accepted bayonets).

T3 Carbines saw service in Okinowa during the last stages of World War II. A battery powered an infra-red light projector and the sniper aimed via a scope which rendered the infra-red visible. The German Army fitted similar night-vision devices to a few Panther tanks shortly before the Third Reich capitulated - scoring some unexpected (though ultimately pointless) victories against American armoured units which lacked their ability to identify targets and aim in the dark.  

Upgraded and redesignated the M3, the weapon was used in the Korean War. It is likely that the 'new' technology which improved the T3/M3 (and gave U.S. tanks night-fighting capabilities) was based upon the late-World War II German technology mentioned above. Neither the T3 or M3 had conventional rear sights - thus they could only used for sniping (with their powered scopes fitted).