A refinement of the M1 Sniperscope developed for World War II, the M3 is an active infrared device which allowed vision in total darkness at up to 125 yards, as well as detection of infrared light sources (such as enemy IR sights and flashlights modified for signaling purposes) at up to a mile. Measuring 16 1/2" long and 10" tall, with a 5 3/4" diameter infrared emitter on top, marked with a Corps of Engineers/ Capehart-Farnsworth label on the rear, and the right side has an ID plate with "3771" serial number. The unit intended to be installed on M1 carbines via a steel bracket on the barrel and rear sight base that is included, with this lot. This scope is complete in the original M3. In a U.S. marked transport case which bears a Capehart-Farnsworth tag and inventory list inside the lid. This rig is complete with the front pistol grip assembly, the power pack, battery pack rubberized canvas case, a "RMC" upper hand guard modified to accommodate the front mounting bracket, spare fuses and numerous light bulbs, and an RCA image tube.