If you are a pen nut like me, you will be curious if these fit the Tradio line.
Sadly, no. There is a little wide part (I'll call it a collar) that's not on the
However, these refills do fit great in my Pilot Vega Gel (aka Dr Grip) pens --
with the chubby barrels. There's obviously no eraser on a Vega pen, but I like
the heft, and anyway when writing with the Frixion pen you have to uncap,
anyway, so may as well just use an external eraser.