A tachometer designed to operate by harmonic action of a reed(s).
NSN 6130-00-106-3557
NSN 4140-01-364-1356
NSN 5925-00-275-7599
NSN 7035-01-322-8180
NSN 5905-01-382-4955
NSN 6320-00-004-9158
NSN 6220-00-870-0788
NSN 5905-01-017-8117
NSN 7035-00-541-8516
NSN 6610-00-097-5176
NSN 5895-01-585-8917
NSN 5835-01-475-5714