The “Grate” floor drain is used in moderate traffic areas where waste water contains sediment or debris and floor construction requires shallow drain body. The collar serves as an anchor in on-grade locations and as flashing clamp when installed in waterproof floors. Manufactured and assembled in the USA by Plastic Oddities, “Friend of the Plumber”. Threaded brass inserts allows attaching the molded in weep hole clamping collar. The drain allows for a 24 square inch flow area. Quality Plastic Oddities parts – since 1975.