Translations:Bulb filler/2/en

The system involves the direct use of the pen barrel as a reservoir, also allowing, when this was made of transparent material, the visualization of the ink level. Filling is carried out by pressing a rubber pump, similar to that of a dropper, inserted directly on the bottom of the body of the pen, and which can be accessed by unscrewing the bottom of the pen. Given the need to have a pump of sufficient size, this generally involves on this type of pen a much longer blind cap than that used on other filling sistems, such as the button filler or the piston filler.