Our Automated Vinyl Covers are run by a hydraulic “direct drive” motor which opens and closes the cover by turning the key. The cover runs up and down in a track system and is the ULTIMATE SAFETY COVER OPTION on the market not only because the electrical motor, called the Power Pack, is removed from the immediate pool environment but is located next to the Pool Pump. No electrical motor is installed within a meter from the water area. Works well for both small to very large pools.