Mabuchi 9VDC constant speed tape deck motor type EG-510ED-9F2 was made for various cassette or tape deck units such as the AKAI AJ-500FS. It features operation from 9VDC, constant speed, built in speed adjustment circuit board with fine adjustment slot on bottom. The high quality motor is 1.5" dia. x 1.37" long and has 10mm long x 2mm dia. shaft. Speed is 2400RPM. Our motors are New Old Stock.