QUICK STABILIZATION – Quick-stabilizing 10-Ounce bob steadies within 6 seconds MULTI-SURFACE CONNECTION – Includes setting pin for wood/drywall, strong magnet for steel surfaces, and hook for nails or studs SELF-RETRACTING LINE – Universal plumb bob setter with 14.5 ft self-retracting line for quick easy storage AUTO-RETRACTING PIN STRIKER – Auto-retracting pin striker for use with a hammer for overhead setting PREMIUM QUALITY – Commercial grade plumb bob for long lasting durability