A rear sight for a handheld weapon. The rear sight includes a tubular device that includes a tubular member comprising a material capable of transmitting visible light so that a target may be viewed through the tubular member, the tubular device, when mounted on a weapon, having at least two circle-like images at different locations along the length thereof that are visible when aiming the weapon on which the sight is mounted at a target by viewing the target through the tubular member. When aiming the weapon, a user will look through the tubular member towards the target and for proper alignment with respect to the target, will maneuver the weapon until the circle-like images are concentrically disposed. This constitutes a simple operation that can be quickly performed, particularly also in low light conditions.