We stock the R-4C7NP for the Ohto 2+1 Multi Pen. It is a 67mm 'D1' format refill however suitable for most multi pens and also the Minimo Tiny Pen
The Multi Pen comes with Black and Red refills and the Minimo come with Black as standard, but we also stock Blue in case you prefer to swap.
The R-4C7NP is unusual in being a fine needlepoint refill with waterproof ink.
The Numbers:
R-4C7NP
0.7mm Refills
67mm long, 2.4mm diameter.