The Waterway Hi-flo Suction, shown with nut adaptor, provides 100 GPM to pump. 3.765" Diameter x 1" Depth to wall. It uses a 2 3/8ths to 2.5 inch hole saw. The plumbing size is 1.5 inch supplied this way. See also the 640-3340 for a 2 inch version. This suction is not in compliance with the Virgina Graeme Baker Act. Waterway has made a suction fitting that is in compliance its part number is 640-3580V