The lower 1/3 co-witness height is 40.4mm (1.6 inches)

BCM Lower 1/3 Cowitness A/T Optic Mount for  M R O

Capability in the face of the unexpected and catastrophic, the Lower 1/3 Cowitness Mount is built in anticipation of a “no fail” shot that will save another human life.

Improving on Mil-Spec rail interfaces dating back over 30 years, the Lower 1/3 Cowitness A/T Optic Mount delivers unprecedented zero retention on a properly mounted red dot optic. Low profile and snag-free, BCM A/T Mounts are built with a minimal number of components - delivering a stronger component with less points of failure, ready to take on dynamic and adverse settings.

Each A/T Mount features multiple integral recoil lugs to mitigate recoil and counter recoil to preserve your zero and ensure “no fail” shots are placed where intended by the trained rifleman.

Each  billet mount is hard coat anodized. 

A/T (Angled Torque) mounts employ angled torque through a  clamp which applies triangulating force to create a stronger and more reliable lock up of the mount onto the end user’s rail. To retain the hardware in field conditions, this system uses a serrated locking spring-washer to prevent the loss of torque on the shaft nut.