If you have a continuous rail, low rings will not fit*. I used the mount and it's solid. The large rings appear to work on paper. Don't listen to the internet ninjas.
* Unless you have a dremel and willing to use it. You might have other issues if you're thinking about doing it.
![](https://static.wixstatic.com/media/dfac6a_9e7a2e89f0684942a86667d8da5028a9~mv2.jpg/v1/fill/w_980,h_640,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/dfac6a_9e7a2e89f0684942a86667d8da5028a9~mv2.jpg)
![](https://static.wixstatic.com/media/dfac6a_d1e8354a05e346b889f5907841e85a87~mv2.jpg/v1/fill/w_980,h_772,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/dfac6a_d1e8354a05e346b889f5907841e85a87~mv2.jpg)
![](https://static.wixstatic.com/media/dfac6a_6da72caf97394e11bc8cdc8f0030f2ae~mv2.jpg/v1/fill/w_980,h_590,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/dfac6a_6da72caf97394e11bc8cdc8f0030f2ae~mv2.jpg)
I had the same issue with medium rings. It touched, though barely, too close for repeated usage.
Well I ordered the medium, hope it works out since I too have a flat rail AR