These Kidco Extra Tall Center Gateway extensions are made of reinforced steel, and protected with a non-toxic plastic coating. They add up to 5 1/2" per unit, up to a maximum width of 47 1/2" with the use of two extensions. When used in conjunction with up to two of the 12 1/2" extensions, the Kidco Extra Tall Center Gateway will fit openings up to 73 1/2". | 
