US Patent 7921591 Flip-up aiming sight

An aiming system having a two-tone colored rear sight lens as the primary aiming component. The lens is held in an L-shaped lens frame which also incorporated conventional “iron sights.” The two-tone colored lens has an outside perimeter portion of one color and a central portion of another color. The lens frame can fold or rotate forward from an upright locked position to a locked-down position using a manually activated one-handed operation.