Manual Brock String, For Eye Examination, Voltage : Non

Brock Strings consist of a white nylon string 10 or 12 feet in length with three (3) small wooden beads of different colors. Alternate models are 6 or 12 ft with 5 beads. They are used for treatment of convergence insufficiency and other anomalies of binocular vision as well as to disrupt suppression. During therapy, the end with the stick is held near the tip of the nose while the other end with the loop is hung to a fixed point like a door knob.