This device is getting many compliments. It is comfortable, versatile and an inexpensive spreader system. The cuffs are made of heavy duty nylon on the outside to hold the strongest prisoners, yet comfortable neoprene on the inside. The spreader mid-section is rigid so they can not adjust their position. The mid section is made of nylon with a reinforced bar underneath. Cuffs secure using heavy duty Velcro. The ankles are 40 cm apart while the wrist are 23 cm apart. There are a variety of fun positions to secure your partner in. Great for doggy style action.