Material: The 700g pool filter balls are made of polyester, polypropylene and acrylic fibers. Good elasticity, non-toxic, stable. 700 g of pool filter beads correspond to 25 kg of filter sand. Powerful: Fast filtration, high adsorption capacity, long service life and easy application. It can trap tiny suspended solids that cannot be easily precipitated and removed, making the pool cleaner. Long Life: Unlike sand, the pool filter ball will not clog not your filter and requires less backwashing for maintenance. Lighter, more comfortable and more efficient than traditional sand filters, perfect alternative to sand filter sand, filter glass and other glass media. Repeated use: it can be cleaned regularly, machine washable , recyclable, very resistant and low loss. (Tips: Place the filter balls in a laundry bag and machine wash) Widely Used: Suitable for swimming pools, aquariums, filter pumps, aquariums and other media.