Hey Culpeper !
The parachutist's adjustable individual weapons case, M1950 is described in TM 57-220 Technical Training of Parachutists, June 1968. You can get a copy here at Global Security.
See also FM 57-230/TO 14D1 -2-1-121 dated September 1989 which describes how to rig the ALICE pack and the M1950 case as a tandem load to lower on the same lowering line.
Regards, Stan
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