Custom designs are any design that is other than a single standard character such as A,B,C,1,2,3. All Freeze brands are made of solid brass designed for freeze branding.  Please note that the material used in our freeze brand is not designed to withstand the heat required to "HOT" brand an animal. If you require both a Freeze brand as well as a Hot brand, you have the option to purchase one of each or you can use a Stainless Steel brand to accomplish both types of branding.