Oshkosh Tachometer / Hour Meter Gauge, p/n 68778AX. Also Ametek p/n 535DI-46733. 0-3500 RPM, 24VDC. Code 06046, used on fire-fighting trucks and other heavy vehicles and engines. Housing measures approximately 3-1/4″, bezel is approximately 3-3/4″. Original invoice on these is $134.12 each. Get it here and save money. 14237 R3B4