Pocket holsters are highly recommended for the safer carry of pocket pistols, with standard practice being to carry the holster (sometimes with a second magazine sub-pocket stitched into the holster) in a front or rear trouser pocket with nothing else carried in the pocket that could snag on the gun when drawn. The most popular pocket holster designs are typically made of form-fitted leather, with a heavy layer of leather worn outward from the body to prevent "printing" of the gun outline on tight clothing, although Kydex holsters are also used, especially for thicker pocket pistols for which the added thickness of a leather holster would cause an excessive overall thickness. The use of moisture and vapor-barrier layers in the holster stitched closer to the body in the holster is recommended to prevent damaging the finish of the pocket pistol due to sweat. This extra layer also serves to increase carry comfort, and to prevent chapping or blistering the skin under the holster due to repetitive motion rubbing or friction that can occur while walking, jogging, or running.