Gardner Bender offers a complete range in various knockout sets. The four-point knockout punches and dies are designed to punch clean, round holes through mild steel or other soft metals. Sizes are available to specifically permit fast and easy installation of electrical conduit and pipe in all commonly available increments. Gardner Bender dies are interchangeable, in any combination, with most brands of knockouts. Constructed from black oxide coated, hardened and tempered chrome-moly steel. Whether you need an entire knockout set, or you're looking for a replacement part for an set you own, Gardner Bender has versatile, durable hole-making products that contractors depend on and ask for by name.