The Velcro® assisted, D-ring Strap wraps around your chest and the back of the chair. The Strap is 2" (5 cm) wide and has a usable circumference of approximately 42" to 52" (107-132 cm). The forehead rest of cycles is not designed or intended to prevent a loss of trunk balance. It is the responsibility of the user or therapist to decide whether obtaining and using the Strap is warranted by one's physical limitations.