Bench Dog

A bench dog is a peg, pin, or stop that fits into a row of matching holes bored into a workbench top, used in pairs (or with a vise's own built-in dog) to clamp a workpiece flat against the bench surface between them. Raising one dog and pressing the workpiece against it while a vise-mounted dog on the opposite end applies pressure holds a board securely for planing or other hand-tool work, without a single separate clamp needed.

Round dogs fit round bored holes; square dogs need a matching square mortise -- most commercial workbenches come pre-bored for one or the other, and dog spacing is generally set to accommodate a useful range of workpiece lengths without needing an impractical number of holes.