The VP-25AA actuators combine precise positioning with highly reliable performance. It is based on the same innovative design used in the VP-25XA linear stages (see Precision Compact Linear Stages) and features a high-resolution linear scale for exceptional repeatability and accuracy. The scale is fixed on a moving rail to which the actuators tip is permanently attached without any contact to the mounting shaft. This concept eliminates all drivetrain induced motion errors and minimizes hysteresis between the scale and the actuator tip. The non-rotating tip is essential to avoid undesirable periodic motion variations caused by variable contact made between the actuator tip and the mating surface.The top rail of the VP-25AA can also be used as a single-rail linear stage to position optical fibers, micro-optics, sensors, or other small and lightweight parts. For added versatility, a mounting interface for a dovetail rail compatible with the popular ULTRAlign positioning system is provided. This system offers a wide selection of interchangeable mounts for optical fibers, fiber arrays, objectives, or GRIN lenses see ULTRAlign Fiber Alignment Accessories.