Eazypower 81379 Two-Inch Get It Out One Way/Rounded Screw Remover.584-Inch #15 Removes stripped or broken screws or bolts Strong enough to drill into hardened bolts Handy storage case #15 one way screw/rounded bolt remover/installer fits 37/64 inch (.575in. 14.77mm) diameter screws Patented one way screw remover/installer is eazy as 1, 2, 3. 1. Loosen set screw to adjust tip depth. 2. Align and seat tip into screw head/bolt. slide collar flush with surface, tighten set screw. 3. Apply pressure while removing or installing one way screw or rounded bolt.