I just got my scope lenses for my Axcel Achieve with their AX-41 scope. These things are awesome and I see why so many pros use them. I am completely impressed with how well this sight performs with a lens in it. So much so I am probably going to put one in my hunting sight, Axcel Armortech HD. It was super easy to install and I don't know why I haven't done this sooner. Unscrew the front scope Lens Retainer, pull out one of the two Red Spacer Rings, replace it with the lens in the Lens Frame, screw the Lens Retainer back on and that is it; you are ready to shoot! Good shooting!