The twist lock system enables perfect clamping on the axle. Tilting of accessories is no longer possible and the annoying problems with the combination "securing groove and ring clamping" are a thing of the past. By turning the upper ring, the ring closes perfectly around the eyepiece and optimally centers it on the axis. A slight tightening is enough to achieve a very stable clamping, as it is really clamped over the entire surface.
In addition to centering, the system has the advantage that it can be easily operated with gloves and also carries heavy loads.