Our dog products are made from heavy leather that will develop a patina with use, no matter which leather colour you choose. It's especially the lighter leather that changes colour with time. The light leather in the colour "natural" will develop a nice glow and a darker colour. How fast the leather colour changes depends on how you use the product. We recommend that the products are not exposed to water (we advise you to remove the products from the dog when it's going to take a bath, etc.). If you choose to expose the products to water you can expect the patina to develop faster. The leather can also become stiff. If that happens you can treat it with leather grease.