Singer Touch & Sew Rotating Hook Driving Shaft Bevel Gears, set of three. Includes Front #174204AS-2 and back #382877l rotating hook drive shaft gears. Plus Upright Angled Arm Shaft Bevel Gear #174204AS-1. All have set screws. Numbered for Singer 620, 625, 626, 628, 629, 630, 635, 636, 638, 639, 640, 645, 646, 648, 649 machines only. Be careful when using these as they need to be precisely set. (Singer sells them mounted in calibrated sets only). Price includes shipping.