Sheer thongs are as close as you'll get to wearing nothing at all. Thongs, with their v-shaped back that tapers to a very narrow strip, leaves the behind exposed. Add to that the bare-all look of an almost transparent sheer material and you have panties that are sexy and almost invisible under clothing.
The fabric may be a sheer open-weave mesh or other lightweight modern material, such as nylon or polyamide. The material will usually have some spandex to create a body hugging stretch. Today's sheer thong styles often have seamless sides, flat elastic and low-rise styling to work under popular low-rise fashions and clingy knits.