Introduced by PI (Physik Instrumente) LP for use with X-Y microscopy stages, the P-737 PIFOC vertical piezo Z-stage features up to 250-μm travel, millisecond responsiveness and nanometer-precision motion under closed-loop control. Its large aperture accommodates a variety of specimen holders, including slides and multiwell plates. For stability and repeatability, the stage is equipped with high-resolution absolute-measuring strain gauge position sensors that are applied to appropriate places on the drive train to feed platform position information to a piezoelectric controller. Typical closed- and open-loop resolutions are 4.0 and 0.5 nm, respectively, and closed-loop linearity is 0.2%. Typical repeatability is 12 nm.