Models? they have different Models? Both mine will be HS510C's, I got them as they were available and had a reticle like Sightmark's 65 MOA circle with 2 MOA dot in middle and they seemed smaller than the bulky Sightmark. They are both for the Warden's AR carbine and AR pistol, same controls will be good. I did not do research much like I did when I first got red dots (Aimpoint PRO's) later I tried others with good but not great success, this time around it was all reticle, a few reviews and we had a winner.