Browning 12534 2 Piece 30mm Standard Burnt Bronze Cerakote Browning's Integrated Scope Mount System eliminates Alignment problems And The Possibility Of a Loose Connection Between The Base And Ring. The Ring And Base Become a Single, Ultra-Rigid Unit machined From 7000 Series Aluminum Alloy. The X-Lock Scope Mounting System That uses Four screws Per Base, replacing The Traditional Two-Screw System. Tube Diameter: 30mm Height: Standard Finish: Burnt Bronze Cerakote Style: 2 Piece Material: Aluminum