Challenge coin Descriptions: Item Coin Material Iron / brass / copper / zinc alloy etc. Size Customer size Thickness 1-5mm Plating Nickel, antique nickel, black nickel, brass, antique brass, copper, antique copper, gold, antique gold, silver, antique silver, chrome, dyed black, pearl gold, pear nickel, double plating and more Surface Soft enamel / Synthetic Enamel / Hard Enamel / Synthetic enamel without polish /Printed etc. Design Customized logos and designs are welcomed