The ceramic disc cartridge is the heart of the faucet, controlling its temperature and water flow. Internally, two opposing discs made out of ceramic carbide rotate to control the flow of water. Because ceramic carbide is impervious to friction, it can last for many years before needing replacement. Solid brass body and stem with 3/8" x 16PT teeth on spline count for the handle. The cartridge thread size is 1/2-14 NPSM. Featuring an M24 x 1.0 threaded collar, and a rubber O ring at the bottom.