The water filter base is made of plastic, is white/blue in color, and is used to connect the water lines into the water filter and hold the water filter in place. The water filter lines have a blue release collar at the top. If the O-rings have gone bad, the filter is leaking, or the locking device has failed and the water filter is not locking in, you may need to replace the water filter base. This is a genuine OEM part sourced directly from the manufacturer. Please remember to shut off the water supply and to disconnect the power to your refrigerator before starting your repair.