This Housing Cap Screw is for use with the following pump series and models: Super Pump VS SP2600VSP, Super Pump SP1600X and SP2600X and MaxFlo SP1800X and SP2800X. It is threaded to provide extra holding strength. With the pool as the centerpiece of the rapidly growing Outdoor Living market, Hayward is prioritizing innovation, efficiency, and comfort. We’ve built industry-leading equipment, filters, and pumps for over 100 years, and today, we are at the forefront of innovation for pool and outdoor living technology and internet-connected homes.