Altimeter, Sensitive AN5760-2, C-12, US Army Air Force, Kollsman, WWII
The Army AN5760-2 Type C-12 Sensitive Altimeter was used across a number of US Army Air Corps and Air Force aicraft during WWII, including heavy bombers B-17, B-24, B-29, medium bombers B-25 and B-26, as well as light bomber A-20, according to the Accessories Interchangeability Chart dated Feb 1945. It was also used in versions of US Army Air Force WWII fighters P-38, P-39, P-40, P-47, and P-51, as well as transports C-46 and C-47. This example was made by Kollsman, part number 671K-03.
According to the spec sheet in the Index of Army Aeronautical equipment Volume 6 Instruments, dated 1944, the AN5760-2 sensitive altimeter has three pointers so that altitude in feet may be accurately indicated. It also has a barometric scale, which indicates atmospheric pressure in inches of mercury, and altitude setting ~reference) markers, which are operated by a knob located at the lower left-hand corner of the case.
It is in reasonable condition given its age. The knob rotates the barometric scale display. Just needs a little cleaning.