And now for something different--a big shiny aluminum bolt. How is it different from all the others, you ask? How about a hollow center and removable "nut"? Conceal various secret goodies inside and place on a desk or shelf in plain sight. Is it a cutting-edge piece of desk art, or a "stealth" safe? It's both! Polished aluminum finish. Made of recycled aircraft aluminum. Hollow with removable nut base. 8 1/4" long. 4 3/4" wide.