C2G/Cables to Go 33100 Keystone Punchdown Puck The easy, secure way to hold keystones for punchdown Say good-bye to stab wounds and marred surfaces Say good-bye to stab wounds and marred surfaces! Our Keystone Punchdown Puck fits in the palm of your hand and securely holds keystones while you punch them down. It also provides a solid surface to ensure proper seating of the wire in the jack.