This bench pin comes notched and ready to use. It includes a keyhole V-slot, indents and a ring-holding extension with sawing slot. Use the recessed oval areas across the middle of the pin to hold components, sizing stock or trimmings while you work. Slip the L-bracket (included) through the hole at the back of the bench pin and into the recessed area; then slide the bracket onto your work surface and tighten the clamp. The clamp accommodates a bench or work surface up to 2-3/8" thick.