The Eco-Friendly Pool Filter Balls are a 1.76 lbs fiber filter system suitable for hot tubs, above ground pools, and in-ground pools. These filter balls are a DE filter system that is designed to be environmentally friendly. They are an alternative to traditional sand filters and are made from recycled materials. The filter balls are easy to install and maintain, making them a great addition to any pool or spa. Equals 63lbs sand.