All Arm Cuffs are made with green recycled materials. Each have authentic copper armature and are sealed with a sealant that makes product at least 80% moisture resistant (from sweat or etc.). But do not immerse in water completely. Each bracelet is hand made uniquely. Some oxidation is normal and enhances the look and feel of cuff. The inside of the cuffs are painted and all are signed by jewelry artist...me.