Ultrahigh-vacuum compatible models 8821-UHV, 8822-UHV and 8823-UHV provide the precision and stability of the Picomotor actuator with greater beam access while offering smooth, reliable motorized adjustment, along with thick front and rear plates. Optimized to improve long-term stability and provide protection against vibrations. They are ideal for UHV environments (10-9 Torr) and well suited for VUV/EUV applications. Available for 1-in., 2-in. or 3-in. optics.