Reference usaf dwg 56b23624, for special markings
A tachometer that is driven through the media of a mechanical connection and includes provisions for fixed mounting.
NSN 5975-01-620-0076
NSN 5996-01-491-0178
NSN 5855-00-167-7893
NSN 6610-00-851-3203
NSN 5990-00-402-1715
NSN 5910-01-391-7774
NSN 6220-00-238-6736
NSN 5895-01-552-6191
NSN 6610-01-097-5073
NSN 6135-01-507-1135
NSN 5895-01-031-0352
NSN 5935-01-364-6758