This Universal Center Ring is designed to accommodate either 2" or 3" shower drains, square drain risers, and most other specialty shower drains. It comes with a 2" or 3" snap-in insert to match the threaded riser portion of the drain. The Universal Center Ring has 24 standard Float Stick attachment slots places every 15 degrees, a 6" inside diameter, and is 1-3/8" high. It is recommended that extra Standard Float Sticks (No. 71513) be used because the center ring which is supplied in the Quick Pitch Standard Kit (No. 71512) is not needed.