Hayward S144T1540S ProSeries 14-Inch 40 GPM Sand Filter System Durable, corrosion-proof filter tank molded of color-fast material for long-lasting, all-weather performance 7-position Vari-Flo valve provides maximum flow at lower pressure drop Large pressure sand/water drain for rapid winterizing or servicing Flange clamp design allows 360-degree rotation for easy installation Integral top diffuser ensures even distribution of water over the entire sand bed for maximum use of the filtration area