These cards are cut to the approximate size of a business card and are designed to be used with most engraving methods. it is also recommended to use an aluminum polish to brighten the contrast of your engravings but is not necessary to the process. Many customers report high success with laser engraving at lower power settings with many different engraving machines and methods. We have also seen these products used for sublimation using transfer paper and heat press as well as metal stamping and cutting. We hope you enjoy these products and have success with your projects!