MATERIAL RELIABILITY: MS Reverse Osmosis (RO) membranes are made from 100% food-grade Thin Film Composite (TFC) material for ultimate purification performance with high permeate flow, tested by an independent third-party to meet NSF/ANSI 58 standards. HIGH REJECTION: 100 GPD RO membrane with a high 97% stabilized salt rejection rate. Hundreds of impurities are reduced by over 99% through the 0.0001-micron TFC membrane layer, including heavy metals (fluoride, calcium, magnesium, lead, colloids, chromium, and nitrates), organic materials, and harmful minerals, including other soluble salts found in water resources. UNIVERSAL MEMBRANE SIZE: Industry-standard element size 11.75 x 1.75-inch, designed to fit in standard 1812/2012 residential-style RO membrane housings utilizing a 2-inch internal diameter. Suitable for most Home Reverse Osmosis Water Filtration system and Maple Syrup filter systems. WIDE COMPATIBILITY: Reverse osmosis water filter replacement for standard membranes including but not limited to Dow Filmtec TW30-1812-100, AXEON TF-1812-100, Desal TFM-100, FLTMEME100, FS TFC TFC-2012-100, MC1. LONG-LIFE: The membrane element, shipped dry in an original sealed package, has a life expectancy between 24 to 36 months, based on average feedwater quality, temperature, and incoming water pressure. Tips: Recommend work pressure is 100 psi when using this product in a Maple Syrup reverse osmosis system. And we suggest heating and maintaining the raw sap at 104°F(40°C) to prevent clog on the membrane while keeping it under 113°F(45°C) to avoid damage to the membrane due to over-high temperature. This is a 5-pack of high-quality reverse osmosis membranes from Membrane Solutions. These membranes are designed to provide excellent water filtration. They have a high rejection rate for TDS, making them ideal for use in home RO water systems, maple syrup DIY, aquariums, and more. The membranes are standard size of 11.75"x1.75" and have standard 1812/2012 RO housings, making them easy to install and replace. With their durable construction and reliable performance, these membranes are a great choice for anyone looking for a high-quality RO membrane solution.