On 4 of my flat tops - Caldwell AR Pic Rail Brass Catcher, Spare Mount

The pic rail mounts for the brass catcher has made life much easier. No more fulling around with velcro straps around scope mounts and sipping down creating an open trap. I have mounted four mount on four rifles in the same position on the rail and only using one catcher in shooting box. I still carry one of the velcro style catcher to use on some of my other rifles or lend to someone at the range.