Pentair IS4 Spa Side Remote, 4-Button, Black, 50' Cable | 521891 Throw Pillow Hayward manufactures cartridge filtration systems

Hayward manufactures cartridge filtration systems widely installed in residential pools

Inspect surrounding seals and hardware during installation

Pump performance is weak because internal flow is not being directed correctly

Includes 3-9-459 as the SKU for quick procurement reference

Compatible with TR100 and TR140C sand filters

Pentair IS4 Spa Side Remote, 4-Button, Black, 50' Cable | 521891 Throw Pillow Hayward manufactures cartridge filtration systemsWhat This Part Is Used For Pentair 521891 IS4 Remote 4 Button, Black, 50ft is a wired remote used with compatible Pentair automation systems. It allows control of selected pool functions from a secondary location. Why This Part Matters A dedicated remote adds convenience for spa or poolside operation. Replacing a nonresponsive unit restores direct control without accessing the main panel. Proper wiring length ensures flexible installation. Key