After market modern replacement electric starter with 10 tooth drive for 59 tooth flywheels. For Mark 55A, Mark 58A (Ser.#1226547 & Up), Merc 300, 4 cyl. Merc 400, 4 cyl. Merc 350(1961), 1961 Merc 500, 1962 Merc 450 (up to Ser.#1479709), 1962 Merc 500 (up to Ser.# 1480087, and Ser# 1480160 thru 1480224)
Same as Mercury model #50-29105K