About This Exclusively for Ontulor S2OP-U1: Designed to fit perfectly with the Ontulor S2OP-U1 Ultra Filtration System (ASIN: B0FHVP293J), ensuring reliable performance and a secure seal. Fine Sediment Filtration: The 0.5-micron polypropylene layer effectively captures visible particles such as sand, rust, and dirt to help maintain clear, clean-tasting water. Durable Food-Grade Material: Made from safe, BPA-free polypropylene that meets NSF standards for household water use. Quick Twist Replacement: Simple twist-and-lock installation allows for tool-free filter changes in seconds — clean, dry, and convenient. 6-Month Recommended Service Life: Replace every 6 months or after approximately 400 gallons of use for consistent water clarity and system performance. Overview Material : Polypropylene (PP) Product Dimensions : 1.5"D x 1.5"W x 8.67"H Item Weight : 2.88 ounces External Testing Certification : ANSI Brand : ONTULOR