Fluval Replacement FX2 Main Seal Part O-Ring. This replacement Filter Cover O-Ring is designed specifically for the Fluval FX2 Canister Filter, ensuring a secure, watertight seal between the filter cover and main unit. Whether you're replacing a worn-out seal or keeping a spare on hand, this O-ring helps maintain optimal filter performance and prevents leaks. Made from durable materials to withstand regular use, it’s an essential maintenance part to support the longevity and efficiency of your FX2 filter system. Key Features: Compatible with Fluval FX2 Canister Filter, Ensures a tight, leak-free seal on the filter cover, Helps maintain proper filter pressure and performance.