This Quick Flip single cross aperture rear sight "The Plus" is new for 2010. The cross shaped aperture is designed to minimize defraction and works well for both flash sight picture shots as well as longer precise shots. The sight is deployed with the push of a button and lock in the folded as well as the deployed position. Made from 6061 Aluminum. As with all Quick Flip sights, they are MIL-SPEC hardcoat anodized. The springs are durable and concealed to prevent fouling.