The face of the boss is square to the bore and made from steel to prevent edges from breaking. The knobs come in metric sizes. They survive service temperatures up to 110°C (230°F) and are tapped or have blind bores. Custom bores, cross pins, and setscrew holes and threads can be requested.

J.W. Winco Inc., 2815 S. Calhoun Rd., New Berlin, WI 53151, (800) 877-8351,