NCStar's AR-15 Scope mount with Quick Release allows you to quickly mount a 30mm or 1" scope onto your Picatinny rail. It is constructed of aluminum with a fixed front Cantilever ring with an adjustable, removable rear ring and includes 1" inserts. This model has a black anodized finish. Features: 30 mm AR-15 scope mount with quick release mount Allows you to quickly mount a 30 mm or 1 inches scope onto your Picatinny rail Front fixed cantilever ring with an adjustable for length rear ring, rear ring is also removable Includes 1 inches inserts, mount works with both 30 mm and 1 inches scopes