We bought one for the hot tub to give a boost to the shorter folks. After adding about a pound of marbles from the craft store it works like a charm. Also bought one to use as a booster seat on the boat, added about 3 layers or dense foam to bolster it up a bit and now I'm not looking through the top bar of the windshield. 10/10 would buy again if I needed one.

Fortunately, I read the reviews and followed what others said about getting the cushion to work. You will need to use something for added weight, e.g. pea-sized pebbles (thats what I used)..or marbles and distribute evenly in the black pouches. I also double-bagged before inserting in the black pouches because I was using pebbles and am avoiding any leak. Put in the hot tub and let sit overnight. THEN, it will work! Note: only 2-3 pounds will work, seriously. The only reason I left off one star is due to the required added work ;)

Problem is it does not stay down in hot tub. It wants to float. If your not heavy enough , impossible to sit on!

I bought the same seat for twice the price Last year. I fill the black three section pouch with 3 bags of marbles from the dollar store. One bag per section. It takes around 24 hrs to sink down in the hot tub. Much better than other booster seats

This booster cushion does not boost at all. Picture is totally deceptive. When you sit on the cushion it flattens like a pancake. Totally worthless as so called booster.