HTRS02 // STROP STRAIGHT RAZOR functionalening // Heavy Duty // Thick Buffalo Hyde. A strop is a surface that is used after the finest stone for the final stage of functionalening. The function of a strop is to polish the edge and work off any burr left behind by functionalening stones. Although other materials are used, strops are most often made of leather. Both suede and smooth leathers, technically known as flesh side and grain side, are used. They can be mounted to a rigid base, like a leather on wood paddle strop, or can be flexible, like a leather and linen razor strop. This strop can be used without any compound. functionaleners of straight razors for instance often prefer using a smooth leather strop with no compound applied. The leather polishes the metal and removes any burr from the edge, leaving it crisp and functional.