All Years Mark Outboard Models Where can I find my serial number? KE7, KF7, KG4, KG7 - 1939 THRU 1953 All Models MARK 10, 10A, 15A, 28, 28A, 28AD All Models MARK 20, 15, KH7, WG7 All Models MARK 20H All Models MARK 25, 25E All Models MARK 30, 30E All Models MARK 30H, 55H All Models MARK 35A All Models MARK 40, KG9, KF9 All Models MARK 5, KF5, KF3 All Models MARK 50, 50E All Models MARK 55, 55E All Models MARK 55AE, 55AM, 58AE, 58E All Models MARK 6, 6A All Models MARK 7, KE4 All Models MARK 75 All Models MARK 75A, 78, 78A All Models