Dear customer, Thank you for choosing our products. If there is any problem with our products, please contact us through the order information. We will be happy to serve you and solve it for you as soon as possible within 12 hours, thank you! Product Instructions:The toilet seat hinges screw replacement parts50mm base has a threaded part, which can help itself expand and tighten when pushed into the hole of the toilet. The rubber stopper can keep a good close fit when tightening the bolt.The round hinge plate can make these toilet hole screws more rigid and fixed. If the current seat accessories are loose, it can only help the toilet seat move on the top. Widely Used:High-quality toilet seat fittings stainless steel plunger, reliable and sturdy fixing kit, specially designed for WC toilet fixing frame.compact design makes it easy to install, quick to disassemble and easy to clean Product Contains:The toilet screw covers include 1 pair of hinge blind hole fittings universal expanding rubber bolt nut screw with washer, designed for toilet pan top fixing. Product FeaturesThe toilet seat fixing kit is great for broken or old toilet seat hinges and fits most standard toilet seats and top fix hinge, specially designed for toilet fixing brackets. Size:Expansion ball diameter: 1.8 cm/ 0.7 inch (unexpanded state). Length: 4cm/1.57 inch; Suitable for 14-16mm hole for 2 toilet seats. Great for broken or old toilet seat hinges. Fits for most standard toilet seats with top fix hinge.