Material: The toilet seat expansion bolt is made of high quality rubber and the screw is made of stainless steel. Stainless steel does not rust like metal, it is not easy to slip, it is not easy to break, and has a longer service life. Dimensions: the screw of toilet seat expansion measures 4cm high, 2.2cm wide at the top and 1.3cm wide at the bottom. Suitable for installation hole diameter 1.3-1.8cm. Dice-shaped design: a word, universal cross nut, give you great convenience and can be installed better and disassembled. Easy to install: just insert the toilet seat screws into the toilet mounting holes and tighten the screws. Convenient and time-saving. Wide range of use: suitable for all toilets that need to be installed.