A choke is a tapered constriction of a shotgun barrel's bore at the muzzle end and is used to increase the range and overall performance of the weapon. This is done by shaping the spread of the shot in order to gain better range and accuracy. For shooting most game birds and clay pigeons, a desirable pattern is one that is as large as possible while being dense enough to ensure multiple hits on the target. Shotguns intended for defensive use often have cylinder or improved cylinder chokes for the widest shot pattern at typically short defensive ranges.