We recommend cowhide, sheepskin and horsehide for their durability. Cowhide is so thick that it is possible to split the skin and have two or more leather hides. The outer skin is the stronger, top-grain portion of the hide. "Full grain" refers to a top grain that hasn't been altered to remove or hide any natural blemishes. Look for top-grain with a thickness between 1.1 and 1.5mm (it's not as durable when it's thinner). Sheepskin is usually soft, reasonably abrasion-resistant, thinner and lighter than cowhide. Horsehide, once quite popular, is thicker than most cowhide, has a smoother exterior surface and is highly abrasion-resistant. Horsehide is naturally quite stiff and takes awhile to break in. For any leather, look for "drum-dyed," a process that gets dye all the way through the hide and softens the skin without degrading strength. Sprayed-on surface coloring will eventually flake and make your jacket look like it's got eczema.