(Click to see larger image) Narishige's HDO-20 is the top-level model of double pipette holder, with all movements oil-hydraulically controlled.

This joint unit enables two pipettes to be placed side by side and controlled from a single micromanipulator. Attachment to the micromanipulator itself, instead of via a ball joint or universal joint, makes it possible to use two different pipettes without a second micromanipulator. The oil hydraulic system is employed to bring the two pipettes closer together and control them without hand vibrations, as with any ordinary oil hydraulic micromanipulator. In addition, the positions of the two pipettes can be preset, allowing instant exchange by means of a lever close to the operator's hand. With its special holder for placing two pipettes side by side, this is a top-level model for pipette holding operations.

Specification