OS item OS-12180 - O.S. motor- 21XZ-B automobile devices motor / Glow Plug needs: Displacment: 3.49cc (0.21 cu.in.) Bore: 16.27mm (0.64 in.) Stroke: 16.8mm (0.66 in.) Practical R.P.M.: 4,000-40,000 r.p.m. Energy manufacturing: 2.55 ps / 33,000 r.p.m. Fat: 362 g (12.52 oz.)