The CPK Concrete Pour Kit is part of the most comprehensive ground mount offering available. It combines the strength of brass and Copper with molded PVC for a durable in-grade installation accessory. Required for installation into hardscape: concrete, stone, tile, or any time grout will contact the fixture. The CPK can also be used in soil, where conduits runs are desired. For use with HWL11, LWL5, and WL16 in-grade luminaires.