A bottle opener is a device that enables the removal of metal bottle caps from glass bottles. More generally, it might be thought to include corkscrews used to remove cork or plastic stoppers from wine bottles. A metal bottle cap is affixed to the rim of the neck of a bottle by being pleated or ruffled around the rim. A bottle opener is a specialized lever inserted beneath the pleated metalwork, which uses a point on the bottle cap as a fulcrum on which to pivot. Varieties There are several distinct designs of such bottle openers. Wall mounted openers are typically found behind bars in pubs, whilst hand-tool bottle openers tend to be found and used in domestic environments. The functional elements of bottle openers (a tooth or lip to catch the underside of the cap, a fulcrum across which to exert the force that will remove the cap, and usually a lever for mechanical advantage) tend to be consistent, although they can vary in design and aesthetics. Crown cork opener Invented at the same time as the crown cork, it is the original bottle opener. But as well as being portable it also comes as a fixed device to be attached to vertical surfaces, often with a tray to catch the bottle tops. It does not open wine bottles. A simple opener is a piece of metal with a rectangular or rounded opening in one end and a solid handle large enough to be gripped between the thumb and forefingers on the other. The opening contains a lip that is placed under the edge of the bottle top, pulling it off when upward force is applied to the handle end of the opener. Speed opener ('bar blade') The speed opener is a flat blade of steel approximately 4 cm wide and 16 cm long with a thumb hole at one end and a letterbox cut at the other to remove the crown seals from a bottle. They go under the names 'speed opener', 'popper', 'mamba', ‘bar key’, and most popularly 'bar blade'. The thumb hole may be used to pull bottles out of ice, by placing the hole over the neck of the bottle, then lifting it. The speed opener is widely used by professional bartenders in Canada, the United States, and the UK. Carried in the pocket or against the body or on a zip string, it is