$45
One of the longest picatinny bases, installed in place of the regular sighting bar, makes it possible to mount collimator or prismatic sights. Due to its length, the range of settings is significantly expanded, which will allow you to choose the best option for each arrow. On the bar there is a sight with a slot, if the optics are not installed, then shooting can be carried out using mechanical aiming. Fixation of the base is provided by 2 screws, one is installed on top, and the second horizontally. When the bar is finally installed, the threaded connections can be treated with a retainer.
Installation on a carbine
