The slingshot bikini/swimsuit has a low cut front, tiny tanga bottom and minimal breast coverage with a clear back. It is tied at neck front crossed or straight. The slingshot is a tanga becayse uplift from the ties in the neck will force the legline upward and inward, the bikini will reveal butt cheeks.

The slingshot emerged in the early 90s when the new spandex fabric became increasingly popular. The stretch of the spandex makes the slingshot fit to perfectly to a well defined body.

Where is it used?
The slingshot has gained a following among female bodybuilder and fitness athletes. It is a good choice to show off your muscles in competition. It is also spotted in strip clubs. On the beach it is more of a niche product and it is sure to give you or your girlfriend a lot of attention. It is probably best suited for destinations with a rather chic or risque clientele. In Europe a slingshot could fit well in on the beaches of St. Tropez, Marbella, Mykonos and Ibiza. Across the Atlantic the slingshot will be a popular accessory if you decide to book a trip to the Hedonism resorts in Jamaica.

Sources:
Illustration Photos from bikini manufacturer the bikini. 
Visit the bikini scientist for more about the slingshot.