Pentek - 20" Big Blue Filter Housing - Blue Cap / Clear Sump - 1" NPTPentek Big Blue 20" Big Blue Filter Housing Blue Cap Clear Sump 1" NPT High flow polypropylene housing engineered for heavy duty sediment and large capacity filtration applications 1" NPT Ports 4. 5" Cartridge Diameter 90 PSI Max Clear Sump The Pentek 20" Big Blue housing delivers the cartridge capacity and flow rates needed for whole house, commercial, and industrial filtration without multiplying vessel counts. The 1" NPT threaded ports and clear