This thing is so cheaply constructed it won't stay zipped.  I purchased for working out. While wearing, the cheap, flimsy, plastic zippers just pulls apart.  The zippers wouldn't even hold when I zipped without any tension or pulling...not that I would even wear it that loose. If you can't get some tension from the belt, it's won't generate any sweat.  The zippers are no good.

 These certainly are not for wearing under clothing.  If you should receive a decent one with working zippers, the 5 zippers are so big, bulky and plastic, you can see them underneath clothing.

The worst thing...I purchased 4 of them. The other people I purchased for can't use them either. What a complete waste of money. This is a ripoff and the manufacturer knows it. I placed my order with the manufacturer online. I should have known I 'd be receiving garbage, when I was prompted, during my order, to upgrade to a sturdier version, for 10 bucks more.  I've finally learned by lesson. For me, no more purchases from "as seen to tv