The Hayward 4 Wheel Suction PoolCleaner features patented self-adjusting turbine vanes that deliver maximum power at any flow, while still allowing the passage of large debris. The 4-wheel drive cleans larger pools, or pools with deep ends, up to 20' x 40'. The patented tire treads enhance climbing ability and obstacle maneuverability, while multiple pre-programmed internal steering sequences ensure complete pool coverage and efficient cleaning.