Off The Wall® allows you to efficiently remove scale, dirt, and stains on most types of pool and spa surfaces including vinyl, fiberglass, ceramic, stainless steel, aluminum and painted surfaces. This new gel formula is specifically formulated for compatibility with swimming pool and spa water. Gel-like formula is 10x thicker than the previous formula 2x faster at penetrating scale deposits Formulated specifically for use in pools and spas Clings to pool and spa surfaces and cleaning tools for easy application and use Long-lasting cleaning for fewer reapplications Even more efficient cleaning of soiled areas than the previous formula Safe for use on most pool and spa surfaces