Material: 304 stainless steel and NBR rubber, no rust problem. Size: 748mm/2.90.3 inches, wing nut for easy installation There are large rubber washers on the upper and lower sides, just apply pressure when installing and keep the wing nut and screw in a straight line, no burrs or other defects Versatile: You can use them to replace toilet bolts in rusted and corroded toilet seats.