Fluidmaster faucet water supply connectors are built to last. Made of a tough polymer core covered with braided stainless steel wire. These connectors exceed code requirements for durability. They also have a large inside diameter for higher flow capacity. The "Click" lets you know it's sealed. Click Seal faucet connectors provide a guaranteed "no leak seal" and eliminate cross threading and stripping. No tools required for installation. 5 year warranty.