GLB Pool & Spa Products 71022 Stain Magnet Swimming Pool Stain Control System Quickly removes metallic stains from pool surfaces, provides long-lasting protection against stains, no draining or pre-testing necessary To prevent future staining, follow stain magnet treatment with sequa-sol, weekly doses of sequa-sol will provide ongoing stain and scale protection Treats up to 20, 000-gallon; compatible with chlorine, bromine, ozone, and salt water pools when used as a system Get the power without the hassle, the two-part system removes and prevents stains; use today-swim today Measures 10.1-inches in length by 6.8-inches in width by 3.7-inches in height