【Material】 The screws and fasteners of the toilet seat are made of high-quality rubber and stainless steel, which are strong, rustproof, anti-corrosion, and durable. 【Design】 The expansion rubber fitting has a threaded part. When you tighten the bolt, it is pushed into the hole to form a secure tight fit. It expands and secures itself into the hole, eliminating the need to install a nut on the opposite end of the screw. 【Product Advantages】 Toilet seat accessories with excellent toughness and stability. Fixes your toilet lid securely and can be easily assembled in minutes. Includes rubber plugs and seals. When the bolts are tightened, the washers compress into the holes for a snug fit. 【Package Included】 4 toilet seat expansion rubber fittings, 2 expansion screws with plastic plugs, 2 additional stainless steel washers. 【Size】 Two sizes of toilet seat expansion rubber accessories included: M6 x 8.4cm (2 pcs), M6 x 5.4cm (2 pcs), M6 x 4.9cm expansion screw, seal outer ring 17mm, inner ring 7mm, expansion ball diameter 14mm–18mm.