For pocket holsters, the external flat side is often the side with a nap, or rougher surface, to hold the holster in place when drawing the pistol. Sporting holsters cover a wide spectrum of styles: maximum access for fast draw shooting, highly adjustable holsters used in IPSC and pin shooting, old-fashioned holsters used in Cowboy Action Shooting, high retention, maximum protection holsters used for handgun hunting, and simple holsters used to hold a handgun while out plinking. Like any sporting equipment, sporting holsters evolve to maximize the benefits given the rules of the game, where applicable, so the competitive sports have the most specialized holsters. Holsters for hunting can be unique if they are designed to carry large handguns or to make allowances for telescopic sights. Large handguns are often carried in holsters that are slung across the shoulder, and removed from the body before the handgun is drawn. Slow access is acceptable in this case because the handgun is not expected to be used for defensive purposes. Categories by method of wear Popular holster types are: Outside the waistband (OWB) or belt holsters, are most commonly used by police and military, and by citizens who choose to open carry. Belt holsters can be worn high and close to the body, slightly behind the hip bone ("4:00 position"), and can be concealed under a long, untucked shirt or jacket. Inside the waistband (IWB) holsters, which clip or mount to a belt and allow one to securely holster the weapon inside the pants. Some IWB holsters give the wearer the option of tucking a shirt over the firearm and holster. A variant design is an "appendix inside the waistband holster" (AIWB), intended to allow wear inside the front of the pants (as opposed to the side or rear, which is more typical). Appendix rigs, a variant design of the AIWB holsters with an attached magazine carrier. Some are modular in design, such as the Dara Modular Appendix Rig. Below waistband (BWB), made popular by Urban Carry Holsters manufacturer, is a style of holster that attaches directly below the waistline and is more deeply concealed than a traditional IWB holster. Shoulder holsters consist of two straps connected in a manner similar to a backpack, with the actual holster mounted to a strap on the right or the left side. Shoulder holsters are designed to position the handgun in one of three ways: