The ACK A30.9 (Mod 9) encoder is ideal for use with most GPS and TAWS systems, and works well with most of today's mode S transponders. Feature Gray code in 100ft. increments and RS-232 in 10 or 100 feet increments. Furnished with a 4 ft. harness, pre-wired jack, quick release mounting tray, fittings, static line, and installation manual. Reports altitude to 42,000 ft. Three Year Warranty.