By the time the leather is boned inside it adds 3/32"in width overall. As to why this holster was designed the way it is, The leather/Kydex makes for a silent and incredibly smooth drawstroke that can not be achieved by one component. The kydex provides a rigid exoskeleton for support and the leather, which is smoothside in, is specially treated to be FAST! There are several competitors that are using the Silent Thunder Champion that have dropped significant time off of their draw. Actually, mitigating finish wear is just an added bonus as it was never included in the design parameters. Fast, smooth, silent,a variety of mounting options, and durable were the set goals for this project. I hope this sheds a little light on this line of holsters.