Institutional quality, meets all high school specifications. 1/2" (12 mm) Tempered plate glass. Made from 1/2" (12 mm) tempered glass set in heavy steel frames and cushioned by shock absorbing vinyl moulding. Steel goal mounting plates are insulated and strengthened by a 1/2" acrylic cushioning plate. 54" x 39" (1372 mm x 991 mm) Mounting keyhole slots are spaced at 20" vertical and 35" horizontal. Can be used with BB-31, BB-33 and BB-34B Goals. Goals must be ordered separately.