This floating solar cover is a great way to save money and protect your hot tub cover at the same time. This cover reduces the evaporation of water by 95% It will save you electricity due to heat retention. It protects your spa covers from the chemicals (foaming) in the spa water, extending the life of your top cover. Please be aware that your blanket may have a join as the material is cut from a 2 metre roll. The 600 micron thermal blanket is very easy to trim into shape with some sharp scissors or Stanley.