Dual manipulator models read from the open end of the U. Large, easy-to-read numerals on scale. Precise alignment to 0.1mm resolution. Triple-start lead screws for fastest positioning possible. Absolute lock at 90°. Universal joint allows scientist to probe in either anterior-posterior or lateral-medial planes. Manipulator. Arm may be swiveled out of the way for convenience in installing animal, or for performing a procedure, and then reliably returned to the same point. Available with 18° or 45° (non-puncture ear bars).