This was Narishige's first water hydraulic micromanipulator specially designed for patch clamping. Its water hydraulic system has a lower coefficient of expansion than an oil hydraulic system, and allows precise movement. A 1:5 cartridge is incorporated to minimize drifting. The large, rigid driving unit enables fine movements and coarse manipulations and a sturdy ball joint is also used. Installation is made more rigid by securing attachments with a double adaptor or an isolation table, eliminating direct attachments to the bar. The drum type control unit has a large handle for precise operation and high linear repeatability. Overall, design considerations are focused on precision movement and stability over long periods of time.

*Separately sold AP-11/AP-13-1 Patch Clamp Headstage Holders mountable.