$31.95Spa Filter Cartridge by Clarathon. Diameter: 7-1/8" Length: 5-7/8". Top: closed castle. Bottom: 2" open EZ lock. Surface Area: 35 SF. Premium Hot Tub Filter Replacement for Unicel C-7335 Filbur FC-3058 Other 1561-01. May replace filters in Dimension One, Elemental Spas, Lowes, and SpaBerry. Always…