This disclosure discloses a restraint device including a pair of bracelets that are adjustable in distance therebetween, while at least one of the bracelets can be dually engaged during a restraint and dually disengaged not during the restraint. Further, this disclosure discloses a sleeve to enable a restraint device to be converted from a “chain style” into a “hinge style” and vice versa. Additionally, this disclosure discloses a restraint device including a first arm and a second arm, where the second arm is elastically coupled to the first arm in order to avoid overtightening when restraining.