This is a WW2 aircraft altimeter, which told the pilot what altitude they were at (normally calibrated within 75’ at low altitudes). Used on many U.S. WW2 aircraft, including the B-17, B-24 & C-47. Manufactured by C.G. Conn, LTD, Elkhart, IN. Sold as a collectable. Not meant for aircraft operation without a calibration check.

A19193