The Penrith Silentium Ultra-Fix® Top Fix soft close is designed for universal pans and is made from durable, Tecnoplast thermoplastic material. The seat features slow close hinges that close slowly and silently preventing slamming and pinched fingers. This seat stays tight with Ultra-Fix® Top Fix: the patented fixing system that keeps your seat tight and installs easily from the top of the pan. No more loose seats!