Illustrator or .eps vector art work is highly recommended. Files like .jpg, .pdf, .tiff, .png, .psd or .bmp are also supportable. Kindly note to enlarge the art work 4 times larger than the actual pin size. (If you need  pin 1 inch then the file need to be 4 inch ).  Also, the use of Pantone Matching System colors in your art work is highly recommended.