Westbrass D493CH-07 Patented Deep Soak Closing No-Hole Overflow Cover for Full and Partial Overflow Closure, Satin Nickel Fits all round, 2 hole overflow elbows Replaces simple covers with a closing overflow for that extra-deep bathing experience Seals against tub and uses O-rings for full closure Fits   all round, 2 hole overflow elbows Replaces   simple covers with a patented closing overflow for that extra-deep bathing   experience Easily   installs with just a screwdriver Provides   greater utility for shallow bathing wells Seals   against tub and uses o-rings for full closure Marks   on trim ring shows overflow level Simple   to use, rotate for a partial closure then again for a full closure