Waterway 25 SqFt Top Load Cartridge Filter with Bypass Valve 502-2510 25The Waterway 502 2510 Top Load Cartridge Filter is engineered for efficient, high performance filtration in portable spas and pools. With a 25 square foot filter area, this top load design ensures that debris, dirt, and contaminants are effectively removed, keeping your water clean and clear. The built in bypass valve automatically releases when water pressure is too high, preventing damage to the filter cartridge and maintaining optimal flow.