BOANN RO-18MPK 18 Month Filter Pack for RO Water Filtration System with Sediment Pre-Filter and GAC Pre-Filter(Pack of 10 Filters) 100% Polypropylene (Stage 1) & 100% Coconut Base Carbon (Stages 2-3+5) Certified Material Particle Removal - Dirt, Sediment, Rust & Other Particles (Stage 1+5) Removes Volatile Organic Carbon Compounds (Stages 2-3+5) Improves Water Purity, Removes Chlorine Taste & Odor (Stages 1-3+5) Quick-Twist Filter Replacement - No Tool Required! FOR BOANN SYSTEM ONLY!