The Trumbull Combination Curb Box Key is made of 5/8” round carbon steel with cast steel combo casting. It features the combination socket that is known for its versatility. This type of socket works well on a pentagon nut as well as a ½” square rod. Moreover, it easily fits on the t-head of a curb or meter stop through 2”. When used on pentagon bolt of meter box covers, the socket of the Trumbull curb box key automatically attaches to lift and hold the lid. This makes it perfect for Buffalo type boxes, although it should not be used with 1” Erie style boxes. Solid steel. Quality built.