The AD-B3-HD modular base is the large base in our modular lineup. This mount is similar to the AD-B3, but it features a second throw lever for added mount security. Standalone it is mount for for the full sized 3x Power ACOG scopes, such as the TA01, TA11, TA31 and the VCOG. Also fits scopes with similar ACOG Style Bases such as the Burris AR-332 and newer model Trijicon RX-30 optics with 3 inline mounting holes. Compatible with the Sightmark Wraith HD and 4K line of Digital Riflescopes. The overall length of the base is 3.5". It is precision machined from 6061 T6 aluminum and finished in hard coat T3 Mil-Spec anodize. It features the Patented QD Auto Lock Titanium Lever system to accommodate both in spec and out of spec rail systems.Features:Does not require proprietary tools for adjustment.Can be adjusted with your finger or a flat blade screwdriver.Lever can be configured to lock to the front or the rear.Superior clamping surface to insure maximum rail engagement.Precision ...