A sex stool is a type of sex furniture that is essentially a low stool with two straps that are spaced apart where the seat should be. This type of furniture allows couples to get into different positions more comfortably, whether they're engaging in oral, vaginal or anal sex.
Example of a standard sex stool.
(Pictured: XR Bangin' Bench)
Sex stools are often made from strong materials, such as wood or metal, and are typically strong enough to support a person up to a certain weight, often 300 pounds. For safety reasons, a sex stool should never be pushed beyond its weight limit as this can cause severe injuries for both partners.