An apparatus comprising a rear sight configured to be coupled with a firearm, the rear sight comprising a left upward member and a right upward member comprising a left horizontal linear alignment indicator and the right upward member comprising a right horizontal linear alignment indicator, wherein a distance between the left horizontal linear alignment indictor and the top surface of the left upward member is less than or substantially equal to the height of the left horizontal linear alignment indicator and a distance between the right horizontal linear alignment indictor and the top surface of the right upward member is less than or substantially equal to the height of the right horizontal linear alignment indicator is disclosed.