Providing anterior and posterior motion restriction, the 631 LSO is the perfect blend of comfort and support, promoting a rapid recovery and return to mobility. Designed to relieve low back pain, the 631 provides a therapeutic level of compression for patients recovering from surgery or injury. One-size adjustable, all braces comfortably fit waists ranging from 24-70 inches* and can be worn underneath clothing. Like all Horizon braces, the 631 LSO can be stepped down to the PRO (Pain Relief Orthosis) for the treatment of recurring back pain.