What is a piston filler?

A pen with the filling pump built in: twist the knob at the tail and an internal piston draws ink straight into the barrel. No cartridges, no converter — the barrel is the tank, typically holding two to three times a converter’s capacity.

It is this site’s namesake for a reason: the piston mechanism is the hobby’s sweet spot of ritual, capacity, and self-sufficiency. The TWSBI Eco delivers it under $40; Pelikan’s Souverän line perfects it.