A-Bolt - Integrated Scope Mount System Integration offers strength and consistency. Browning's Integrated Scope Mount System unitizes the ring and base into a single, ultra-rigid unit. Machined from 7000 series aluminum alloy, they eliminate alignment problems and the possibility of a loose connection between the base and ring. Be sure you have the correct rings. These integrated rings only fit A-Bolt and A-Bolt II rifles with Super Short Actions. They will not fit standard actions or long actions. In general, Super Short actions are chambered for 243 WSSM, 223 WSSM, and 25 WSSM. These also fit 223 models and 204 Ruger versions. No matter what the caliber, these integrated rings only fit A-Bolts with Super Short Actions. A-Bolt is referring to the original A-Bolt, the A-Bolt II and the A-Bolt Shotgun. Bases for these firearms are not compatible with AB3 or X-Bolt Bases. Specifically made for A-Bolt II rifles with Super Short actions. Lightweight integrated scope mount system, unitized base and ring, 7000 series aluminum. Fits only Browning A-Bolt super short action rifles. (Not compatible with AB3 rifles or A-Bolt standard and long action rifles.) Important: Compatible with Browning A-Bolt super short action rifles only. A-Bolt refers to the original A-Bolt, the A-Bolt II and the A-Bolt Shotgun. Scope systems for these firearms are not compatible with AB3 or X-Bolt rifles. Description: Alloy Black Fits all Browning A-Bolt rifles and shotguns Rigid, integrated, one-piece mounting system Machined from 7000 series aluminum for high strength and durability .400" Low height for scopes up to a 44mm objective with a standard barrel contour. .500" Medium height for scopes up to a 50mm objective with a standard barrel contour Matte Blued pockets Two-piece mount Super short action length 1" diameter Intermediate Height 4 screws Bases screws: .25 Ring screws: .375 3.2 oz