The Fifth Corps was organized 18 May 1862, while the Army of the Potomac, to which it belonged, was engaged on the Peninsular campaign. The reproduction of an original is antique silver-finished brass and measures 1.5" (38mm) square and weighs in at 1 oz, or the weight of a .58 caliber Minié ball. It is attached to the uniform or kepi by a barrel-clasp safety pin.