Oatey 42237 PVC Shower Drain with Snap-Tite Square Top Stainless Steel Strainer for Tile Shower Bases, 2-Inch or 3-Inch Low profile for tight spaces Designed for use on built up Shower bases of tile or marble, where a Shower pan liner is used The clamping ring locking bolts screw into brass inserts to prevent stripping Keyhole slots in the clamping ring allow it to be clamped without removing the bolts Four weep holes in the drain assembly allow drainage from the pan liner