Prevent excess water from gathering on your pool covers, both winter and safety covers. This auto-activated pump will detect when water on top of your cover reaches a certain amount (1-1/2" water), and automatically deactivates so it doesn't run dry and grate to prevent cover sticking. No muss, keeps your pool cover safe even in winter storms (25F - 120 F, water temp). Easy to move, portable, durable. Works with both winter and safety pool/spa covers.