American Defense Mfg AD-509T Holosun 509T Lower 1/3 Mount

The AD-509T QD mount is a precision one-piece solution developed for the Holosun 509T red dot footprint, intended for use on AR pistols and other firearm platforms that require a compact, lightweight optic system. It is machined from 6061 T6 aluminum and finished in a hard coat T3 Mil-Spec anodize for durable surface protection. The mount uses American Defense's patented QD Auto Lock Lever system to accommodate a range of rail tolerances while maintaining a secure interface.

Key Specifications

• The model is AD-509T.
• Designed to fit the Holosun 509T footprint.
• The mount size is Lower 1/3.
• Manufactured as a one-piece unit for rigidity and alignment.
• Machined from 6061 T6 aluminum.
• Finished in hard coat T3 Mil-Spec anodize for corrosion resistance.
• Features the Patented QD Auto Lock Lever system for quick-release attachment.
• Color is Black.
• Product type is Mount and subcategory is Optic Specific Mounts.
• Description notes the mount is Quick Release for fast removal and installation.

Compact and robust, the AD-509T QR lower 1/3 mount provides a secure, repeatable platform for Holosun 509T-compatible red dots without adding unnecessary weight. Its combination of precision machining, durable finish, and the QD Auto Lock Lever makes it suitable for shooters who require a low-profile optic mounting solution that balances strength with ease of use.