Guardian Pool Spa Filter Replaces Unicel 6CH-47 Top Load Replacement Spa Filter Cartridge 47 Sq Ft PTL47W FC-0315 Outside Diameter: 6" Length: 8 1/2" (also 9) Top Opening: Handle Bottom Opening: 1 1/2" MPT Threaded, Male Thread Media Weight - 3 oz. SQ FT Media - 47' sqft Unicel  6CH-47 (6CH47) Filbur - FC-0315 (FC 0315) Pleatco  PTL47W-P4 (PTL47WP4)