The 1" Wilkins 350XL Double Check Devices is a Lead Free version of the Wilkins 350. They feature a unique plastic insert cartridge that houses both checks in a compact design and sets into a bronze body. The checks are inline modular design, with self contained check assemblies. Ideal for situations that require winterization, as the whole cartridge can be removed in freezing conditions. A blowout fitting is also available for ease of system winterization. This device is Lead Free compliant.