Bobro Engineering Precision Optic Mount Extended 30mm Rings Black. Some of the more popular Precision Rifle Scope Mounts for Handguns from other brands will work with these Bobro Extended Precision Optic Mounts as well. These Riflescope Mounts & Bases by Bobro Engineering incorporate the patented US Patent 8567105 BLAC lever system which requires no manual adjustment to attain a proper rock solid engagement on a 1913 Picatinny rail. The extra 0.75 forward throw on these Bobro Engineering Precision Optic Mount Extended systems give you the additional 0.75 forward throw needed for rock solid repeat zero scope interface with your weapon platform. These Riflescope Mounts & Bases by Bobro Engineering are built with an auto indexing mechanism which means that the mount will always maintain proper alignment and zero repeatability. Also these mounts are made to be completely tool and user adjustable free. If you need a reliable and rugged mounting platform for your optics then look no further than the Bobro Precision Optic Extended Mount Extended System. Specifications for Bobro Engineering Precision Optic Mount Extended w/30mm Rings: Manufacturer: Bobro Engineering Height: 3.25 in Fabric/Material: 6061-T6 Aluminum Color: Black Distance Between Rings: 2.15 in Base/Mount Type: Cantilever Ring Mount Tube Diameter: 30 mm Ring Height: 1.575 in Length: 6.75 in Weight: 7.5 oz Width: 0.86 in Condition: New Finish: Type 3 Hard coat black anodizing Features of Bobro Engineering Precision Optic Mount Extended w/30mm Rings: The Precision Optic Mount features the Patented BLAC lever system which was designed around the following parameters: Must be compatible with any 1913 Specification Rail to include systems that are out of specification (within reason) and this includes Weaver rails. Must be completely tool and user adjustable free It needs to be 100percent self contained and mate securely to any rail without the user having to tailor the pressure/engagement position. Must lock with enough pressure to positively attach any device or optical instrument to a rail without movement static or dynamic forces not withstanding. The rail must not experience any deformation due to user error This must include synthetic (plastic/polymer/composite) rail systems. Auto Index capability The device must also index parallel to the bore The unit must always repeat the forward shift (recoil forces direction of influence) not only to maximize zero repeatability but to take this step of installation out of the users initial mounting sequence Index must be redundant. Unit must not shoot loose due to improper mounting or a mechanical bottoming out. The system must incorprate a safety that prevents the lever from being accidentally opened The safety must be able to be manipulated in conjunction with the lever rotation so that only one hand is required to open it. The unit will utilize constant force to ensure required pressure in all conditions The force must be substantial to prevent any shift forward/aft left/right. The pressure must be applied in a linear direction centered in the main body to prevent cocking of the mount. It must be easy to manipulate by gloved or fatigued hands. It must be extremely robust and withstand shock and impact to the system housing. There were others but by listing them we would compromise our trade secrets. Included Accessories: Instruction and Toolkit Package Contents: Bobro Engineering Precision Optic Mount Extended w/30mm Rings Bobro Engineering B03-202-300: Precision Optic Mount Extended 30mm Rings Black