Not a lot of information on this holster. But I did find this.

“... THE M4 HOLSTER WAS DESIGNED TO CARRY THE COLT & SMITH & WESSON .45 CALIBER REVOLVERS WHICH WERE BOTH STILL BEING ISSUED & USED IN LIMITED QUANTITIES DURING WWII. SIMILAR TO THE ( M2 ) 1917 HOLSTER, THE DIFFERENCE BEING THAT THE ( M2 ) WAS DESIGNED WITH A BOTTOM PLUG, RING & TIE DOWN THONG, & THIS ( M4 ) WAS DESIGNED ONLY WITH A SLENDER CLOSED, STITCHED BOTTOM WITH BRASS EYELIT DRAIN HOLE, BY WHICH AN ELK LEATHER LEG THONG COULD BE THREADED THRU & TIED OFF FOR SECURING TO THE WEARER’S LEG. AS WITH THE ( M2 ) THIS ( M4 ) WAS DESIGNED TO BE CARRIED “BUTT TO THE REAR” AND WORN ON THE RIGHT HIP. THE ( M4 ) IS CONSTRUCTED OF RUSSET LEATHER CONSISTING OF 4 SEPARATE PARTS, THE BODY, FLAP WITH STUD SECURING HOLE/CATCH, BELT LOOP & WELT, ALL SECURED BY (8) BRASS RIVETS AND HAS THE FRONT BRASS CLOSURE STUD. THE FRONT OF THE ( M4 ) IS EMBOSSED WITH US IN AN OVAL CIRCLE & MAKER STAMPED & DATED ON THE BACK OF THE BELT LOOP BY EACH MANUFACTURER...”

And,

“... SEARS SADDLERY RECEIVED THEIR CONTRACT TO PRODUCED THE M4 HOLSTER IN 1942 & PRODUCED THEM FROM 1942-1944.
SEARS SADDLERY MARKED THEIR HOLSTERS ON THE REAR BELT LOOP WITH – SEARS “ONLY”
MILWAUKEE SADDLERY RECEIVED THEIR CONTRACT TO MANUFACTURE THE ( M4 ) IN 1944 & SUPPOSEDLY PRODUCED THEM FOR 1 YEAR IN 1944 ONLY.
THEY MARKED THEIR HOLSTERS ON THE REAR BELT LOOP WITH - U.S. MILWAUKEE SADDLERY AND THE DATE – 1944 ...”

Kevin

__________________
Unshared knowledge is wasted.