Add the ZWO EAF hand controller to the standard version of the ZWO EAF for quick and easy focusing of your telescope's focuser. The EAF HC is super easy to use. It features IN and OUT arrows for focusing as well as a slow/fast speed rate control slider. Plug the hand controller into the "Temp/HDX" port on the EAF, located next to the USB port and start controlling your EAF-enabled telescope focuser today!