That's a group of ladies modeling something they call the invisible bra. It isn't actually invisible, of course. But because it doesn't have any straps and is flesh colored it gives the illusion of wearing no bra at all.
From the back it does indeed look like she is not wearing a bra. With a mesh top like that it could be scandalous, which is what a lot of ladies will be going for when they wear it.
Here is the first step for "installing" the invisible bra. It has adhesive strips on the sides of the cups. The cup must be held in place against the breast and the adhesive attached at the sides.
Then the cup is smoothed across the front and sides
Finally the hook is attached at the front.
That's the completed installation. I'm not sure why she is holding a tape measure. I don't think they claim it increases your bust size.