This patented clear plastic ring is designed to keep mortar from the weep holes in a drain. The ridges of the Positive Weep Hole Protector™ allow for water to flow underneath the mortar and into the weep holes. The inner and outer diameter of the disk are perforated to allow for customization depending on shower drain size. This ring is designed to sit on top of the bolt flange and under the Quick Pitch Center Ring or Universal Center Ring prior to installing your mortar bed. A Positive Weep Hole Protector is recommended for every shower application using a 3 part drain system.