With this Flowclear pool cover from Bestway, you can prevent dirt, leaves and waste from getting into your pool. The above-ground pool cover can prevent algae growth and reduce expensive replacement chemicals. The cover is made of PE (polyethylene), which makes it tear-resistant and water-repellent. This pool cover has drainage holes to prevent water from collecting on the cover. Thanks to the ropes supplied, the pool cover can be firmly attached to the pool.