The LUCID Optics PRO series QD 30mm mounts include the top ring with a sensitive Anti-CANT device designed to help eliminate inadvertent rifle tilt in precision marksmanship. These mounts are well thought out and a quality platform for the connection between your rifle and the optic. \n \nSPECIFICATIONS: \n* 6061 Aluminum \n* Anodized Matte Black \n* QD Attachment \n* No Proprietary Tools Required \n* Weight: 7 oz. \n* "Blue" Anti-CANT level included \n* Lifetime Warranty