Onoto 1000 shut off Plunger

This plunger is specially designed for the LEAKPROOF  1000 pen also known as 'the long slim ' model, and has been produced using original specifications.

It is attached to the rod by a 5ba left hand thread and is black in colour. The main body and the shut off part are assembled using the same 5ba L/H thread which ensures a good seal with the washer

This plunger has an ink shut off cone in the design and does not require a hard backing washer behind the rubber washer.

Each plunger purchased comes complete assembled with a 7.78mm diameter rubber washer  and is held together with a 0.85mm diameter pin