ALIO has developed ultra high precision rotary stages to meet and exceed today's demand for high precision motion. Mechanical Rotary Stages: Mechanical bearings rotary stages have been design with crossed roller bearings for improved stiffness for off set loads and rotational precision. The ALIO attention to materials and machining is maintained in the rotary product line as with the linear products making sure the bearings and metal are located in ultra machined parallel surfaces. (Notice the precision lands on the top of the AI-80R-D picture.) ALIO stages have a standard 0.2 arc second resolution with the ALIO supplier motion controllers. Typical standard mechanical crossed roller bearings are rated at 20 microns or radial and axial runout with optional 6 microns is also available.