Description US/C-3a Infrared Viewer (AN/SAR-1) with carrying case. Model MI-2558, Serial no. 1657 Manufactured by RCA Contract No. NXss 29734 May 1943 - January 1944 The device is a handheld or searchlight mounted receiver used to convert infrared to visible images. Working range with the type H hood is 10 miles. The receiver is 12" long, 13" with the carrying case. Total weight with the carrying case is 9 pounds. The set uses 117N7GT/G, 165A, and 1P25 vacuum tubes. This set is operational. It uses 115 volts AC. The C-3a superceded the battery-operated C-3. See AN/SAR-1 data sheet (1 page).