These filters out perform the alternative filters in durability and effectiveness.
Hot Spring C30 Filter Cartridge Fits: Solana Spas (all model years) Solana SZ square with plastic or redwood sides Solana TZ Triangle Solana RX Round with plastic sides Hot Spot Spas (all model years) TX SX Stride Propel Highlife Spas (all years) Jetsetter Sovereign Prodigy Triumph Aria Envoy Vanguard Grandee Vista. Filters made from high performance silicone with central contortion band.