Laguna Quartz Sleeve Flange for Pressure-Flo Pressurized Filters Reversible argyle raincoat Fits Laguna Pressure-Flo pressurized filter models 700, 1400, 2100, 3200 It is a retaining device that holds the quartz sleeve to the UVC head on Laguna's Pressure-Flo filter The flange is installed using two screws Measures 3/5-inch length by 3-1/5-inch width by 5-2/7-inch height