Sioux Chief Plumb Perfect Series 100% corrosion proof Nylon closet bolt; lab tested to exceed 1,100 lbs. tensile strength per bolt; designed for smoother, faster threading; with unique bolt base which preloads into any flange and eliminates the need to double nut; nut is sized for 1/2 socket or nut driver; for use with bolt caps, resists damaging china due to over tightening.