The Jacobs Super Chuck #18N is a high-quality ball bearing drill chuck with a capacity range of 1/8 to 3/4 inches. It features a 4MT arbor and 4JT taper mount, making it compatible with various drilling applications. The keyed chuck design ensures secure attachment to the drill, providing accurate and reliable performance. Ideal for CNC machining and metalworking, this chuck from Jacobs Super is a reliable tool holding accessory for precise and efficient drilling tasks.