NEW OLD STOCK This listing is for one (1) Boston YJ18 industrial timing belt sprocket or gear pulley. This robust metal component is designed for demanding applications within metalworking, manufacturing, and CNC equipment. The part features a keyway for secure shaft mounting and is marked with the Boston brand and model number YJ18. It is an ideal replacement part for maintaining or repairing machinery requiring a durable and precise power transmission component. Please examine all images carefully to ensure compatibility with your specific equipment needs. Sold as-is.