1pc Spur Gear pinion 1.5M 40T 1.5 mod gear rack 40teeth bore 6-20mm spur gear  45 steel cnc pinion  high frequency quenching 1pc spur gear pinion 1 5m 65t 1 5 mod gear rack 65teeth bore 10mm 12mm spur gear 45 steel cnc pinion high frequency quenching