Sinful line Leg Up Sling Black. Sinful Bondage introduces the Leg Up Sling to its acclaimed and upscale line of bondage gear. Thoughtfully crafted for pleasure and comfort, the sling provides fully adjustable neoprene padded neck rest and thigh loops. The perfect leg support for enhanced stimulation during sex. Black anodized hardware for durability and strength, the Leg Up Sling is easy to use and perfect for couples looking to kick their sex life up a notch.