They're officially called shapewear, but they're more often referred to as Spanx - the name of a hugely popular brand. And Bloomingdale's salesperson Meryl Lefkowitz says the right ones can make or break an outfit.
"Spanx are a great staple for any woman's wardrobe. Kind of pulls you in. Makes all those bumps and other lumps, it smoothes them all out," Lefkowitz said.
To see if they can deliver, consumer reports wanted to put shapewear to the test. Four stoic staffers volunteered - wearing a dress they felt could look better on them.
"They let it all hang out for our "before" pictures, then we put them in four different shapewear garments. We had a fit professional come in and evaluate them," Jody Rohlena said.
Consumer reports sized up four shapers. There were two from spanx: the $68 hide and sleek hi-rise body smoother and the $38 in-power line super higher power. Also the $20 assets by Sara Blakely from Target and an infomercial product - the Kymaro new body shaper.
"With Kymaro's new body shaper, you will have a new and improved figure instantly," Dawn Yancy said. "It was just too confining."
"The top of it felt like a torture device," Jamie Hirsh said.
Turns out the $38 Spanx worked the best for three of the women. See how much smoother this jersey dress is.
"It made me feel extremely confident," Barbara Edelheit said.
But the fourth panelist says she felt great in the 20-dollar assets shaper from target.
Just goes to show you don't have to spend top dollar to look fabulous.
And just in case you men are feeling a little left out, there are, in fact, Spanx for men. They're like a t-shirt that acts as a girdle.
A male consumer reports employee gave it a try. It took an inch-and-a-half off his waist, but it was hard to put on and take off and it wasn't very comfortable.