Contains heat Bubble covers prevent heat loss and maintain the water temperature: the temperature of a swimming pool without protection by a bubble cover drops by 4 to 5C each night, while the temperature maximum temperature of a protected swimming pool can drop by 1 or 2C. The evaporation-limiting bubble cover also fulfills two additional functions: it considerably reduces the evaporation of water by up to 90 percent and protects your pool from external contamination and other impurities (leaves, insects, dust). Durable The bubble cap has a thickness of 400 microns, is made of cellular PE (a solid and immutable material ), treated with UV protection and non-stick treatment, meaning it will not mold or change quality. Adjustable Our bubble covers have neither edges or holes, so you can adjust the cover to fit your pool with simple scissors. However, you can simply add grommets without the risk of tearing or fraying. Note: The data is all measured manually, please allow 1-3cm error due to difference in light and color. display, there may be some color differences, please refer to the actual item received. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.