Sun2Solar Blue 7-Foot-by-7-Foot Square Solar Cover | 800 Series Style | Heat Retaining Blanket for In-Ground and Above-Ground Square Swimming Pools and Spas | Use Sun to Heat Pool | Bubble-Side Down

Wish I could rate this item negative 5 stars. It’s made of plastic bubble wrap like you would find as packing material. It’s too think and light weight. When the filtering or heating flow from the spa comes on automatically throughout the day, the slow water flow pushes the light weight plastic around and it just folds up and balls up exposing over half the water surface area. This make it entirely unusable. I have never before seen a more useless product. DO NOT BUY THIS. I demanded a refund.

Go with a heavier mil, this one does the job, but is very flimsy. 16mil does not hold against the jets, harder to lay back in. 16 mil too light.

I’ve bought many pool solar covers. Buying this size is one of the most expensive ways to buy a cover $/sq ft. I usually buy the big rolls but this size was perfect for my built in hot tub. Anyway, if it lasts a year, I’ll be surprised. This is very light weight. I’m sure it will work fine, just won’t last .

Way too thin for hot tub solar blanket. Circulation jets push it into a messed up bundle. It won’t lay flat once jets come on. Suggest everyone stay away. Look for thicker, more stiff material.

Don't assume all bubble covers are the same. This product didn't advertise its thickness. I usually buy 15 Mil covers, this one might be 8 Mil.