Stens 120-927 Primer Bulb Replaces: MTD: 951-10639, 951-10639A, 951-10888b Fits MTD: 161-jw, 161-jawa, 165-su, 478-su, 483-su, 365-square, 490-su, 365-sub, 370-sub and 370-square Od: 1 5/8" Height: 1"