Essential controller design for UNI Fan SL-Infinity Wireless, CL Wireless, SL & TL Wireless, Strimer Wireless, and Hydroshift II. If you purchase a 3-pack of UNI Fan Wireless version or the PW24-1W-T (24-pin Wireless Strimer), one controller will be included. A separate purchase of this L-controller is required for one-pack functionality.