Dawson Perfect Impact adjustable target rear sights for Glock pistols provides a sturdy adjustable rear sight that is the choice of professionals, pair the Dawson rear sight with the Dawson target front sight to give you a crisp uncluttered sight picture. This product is intended to be installed and safety checked by a professional gunsmith familiar with the operation of firearms. DO NOT attempt to install this product yourself. YOU are responsible for the safe handling, ownership, and proper transportation of firearms. Obtain qualified supervision and instruction if you have any questions concerning safe handling and operation of firearms.