SAFE MATERIAL: Pool filter balls is 100% polyethylene, does not contain toxic and harmful substances and does not affect water quality. SIMPLE AND EFFECTIVE: Filter balls has excellent filtering effect, easy to use, good elasticity, light weight, high strength, long working period and low loss, which is more efficient. CLEAN AND COMFORTABLE: Swimming pool sand filtration is economical and replaces 18 kg of sand with 500 g balls. Filter the smallest impurities from the water to bring cleanliness and comfort to the pool. ENVIRONMENTALLY FRIENDLY AND RECYCLABLE: The filter ball is easy to handle, reusable and renewable. The filter balls can be cleaned by machine or manually, saving time and energy. WIDE RANGE OF USES: Pool filter sand has strong functions and is very suitable for swimming pool cleaning. It can replace the sand in the swimming pool sand filter and is compatible with all sand filters.