Floating spa cover saves energy and money through insulation. Excellent for outdoor spas, gunite spas, and poolside spillover spas. Protects the spa's rigid cover, extending it's life up to 70%. Keeps chemicals & ozone from attacking rigid spa covers. Reduces room humidity and condensation for indoor spas. Woven scrim fabric on both top & bottom will last for years. Will fit any spa - simply trim to fit. Ideal for swim spas.