AquaStar HVK101 2" White Hydrostatic Relief Valve - This 2" hydrostatic relief valve is a pressure equalizing solution for high water tables. The valve is easy to install and remove with its fins, and can fit any AquaStar or most other manufacturers' 2" threads. It is made from UV-resistant engineered polymers and includes a 2" x 1 1/2" reducer bushing that must be glued into the valve using ABS glue. This product is made in the USA and helps prevent damage to the pool caused by hydrostatic pressure.