Features: 1.Compatibility: Fit for Whisperflo and Intelliflo pumps, as well as the Intelliflo VSF. It will not work with the Superflo or Superflo VS pump. 2.Durable and abrasion resistant quality materials and well tested by the manufacturer placed through extensive tension test to prove high quality durability and ensure longevity. 3.Function: Used to replace warped, damaged or unsealed pool cover pumps and designed to lock and hold the lid and O-ring assemblies down in place on the pool pumps. 4.The surface is smooth and will not be scratched during installation. Designed with two symmetrical lugs for easy installation. 5.Easy Installation: Simply turn off your system, release any air, and rotate the locking ring counterclockwise. Package include: 1 x 357.