Mirror holder

[Features]
· A new type of lock mechanism which can vary the torque on the adjusting screw (1-5593-11/13/15/17).
· The mirror side is fixed at three locations (1-5593-11/13/15/17).
· By pointing the operational direction of the adjusting screw up, it can be made space-saving and compact (1-5593-12/14/16/18).