Keep spa water circulating and filtering effectively with this Spa Tender replacement filter cartridge designed for applicable Artesian South Seas and Tropic Seas spas. Compatibility includes applicable Tahiti, Waikiki, Oahu, Maui, Fiji, Kona, Rio, Kauai, Hawaii and Lanai configurations. Comparable to Unicel 6CH-502. Always compare the dimensions, end-cap style and original filter number before ordering because equipment can vary by model year and configuration. Replacement filter; not an OEM Artesian or Unicel product.