Aimpoint, the company that designed the first red dot sight, is famous for their Micro small tube sight design which many have tried to copy since their patent had expired. These red dot sights feature a mounting standard that is by far the most popular in the small tube sight category.
The mounting surface is lifted in the middle. On each side of the lifted section, there are two screw holes for mounting purposes. This section is cut in the middle; this cut part is where the recoil stopper on the adapter fits into. The screws are put in place from below.
Red dot sights that feature the Aimpoint Micro mounting standard can be used on rifles; they are too big for pistol use. Usually, they are supplied with a Picatinny platform adapter.
Aimpoint Micro mounting standard - Aimpoint Micro H-1 Footprint
There are plenty of modifications of the Aimpoint Micro mounting standard on the market. The changes often have to do with the design of the lifted section. It can be wider; the screws can be closer together; the recoil notch is sometimes missing, etc.
Most Aimpoint Micro mounts are made from aluminium. They are produced by Aimpoint, EAW, Contessa, Henneberger, INNOmount, MAK, EGW, Rusan, Dentler, and many others.
Aimpoint Micro mounting standard
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