The 4396508 is for Whirlpool - Kitchenaid - Roper - Estate - Kenmore/Sears (106.series) side by side refrigerators with the filter that Mounts Thru Lower Kickplate(Grill).Requires a 'Quarter-Turn' to install and remove. The 4396508 Reduces bad taste, odor, lime scale buildup, chlorine, dirt and rust.Does not remove flouride from your water. Mostly used for Treated (City) Water Applications. For Untreated (Well) Water Applications, use the Better 4396510 water filter.Rated at 240 Gallons or 3 - 6 Months.