Question

How ink in filled up in pen refill???

Answer 1

Detail of the tip of a gel pen

A gel pen uses ink in which pigment is suspended in a water-based gel.[1] Because the ink is thick and opaque, it shows up more clearly on dark or slick surfaces than the typical inks used in ballpoint or felt tip pens. Gel pens can be used for many types of writing and illustration

Answer 2

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Place the fountain pen, nib first, into the bottle of ink until the nib is entirely covered . Twist the piston converter counterclockwise at the top. This forces the air out of the converter. Then twist the top of the piston converter clockwise to draw the ink up into the converter.