This product is a compressed, slow dissolving chemical sanitizer designed explicitly for hot tubs and spas. Product benefits and functions: Continuous sanitation: The slow-dissolving formula disperses evenly to provide constant, long-lasting protection against bacteria and microorganisms. High temperature stability: Unlike chlorine, which breaks down rapidly in hot water, bromine remains highly stable and effective in warm envirnments. Low odor and low irritation: It is an excellent alternative to chlorine sanitizers. It cleans the water effectively without producing harsh smells, minimizing skin and eye irritation. Surface compatibility: Formulated to be gentle on vinyl liners, making it compatible with both soft sided inflatable tubs and traditional hard sided fiberglass or acrylic spas.