The superior suction of these comfortable and durable cuffs works on any smooth surface. for versatile and on-the-go restraint for you and your partner! Just stick the cup to a smooth. flat. hard surface. It is designed to hold strong. with Neoprene lined cuffs with adjustable Velcro closures for comfort and security. Great for men and women. these fun bondage toys are compact and simple. making them a great option for travel and discreet play! Size Circumference: Adjustable up to 10.75 Diameter: 2