1. Fit chest plate A. Modify shape if necessary after first removing occipital component B, discs C, and mandibular component D. Bend horizontally to follow chest contour and vertically to conform to the sternum.
2. Reassemble discs C to chest plate using the two inner threaded holes for small patients or the two outer holes for larger patients.
3. Adjust angle of both shoulder supports so that each passes over the shoulder comfortably between the insertion of the trapezius and the acromion. Tighten screws to lock shoulder supports. Insert pointed setscrews F into the open threaded holes and tighten to prevent shoulder supports from rotating.
4. Fit occipital components B by adjusting and fixing stops E for proper elevation. Insert rod straps into the slots on the chest, close fasteners and bend posteriorly to position the occipital pad under the occiput.
5. Fit mandibular component D by positioning chin pad under chin at correct elevation. Fix in position by setting proper hole over pin. Mark selected hole by etching so that component can be replaced in proper position if it is removed. Close fastener.