What does the F on fountain pen mean?

LeStallion

The majority of pens that can be found at stores that are not considered to be specialists on the High Street will have a medium (M) nib. Although this is going to work for the writing of a lot of people, it is not going to work for everyone. That is why, where it is feasible, we give several different options of nib point size.

The following is a basic summary of the many kinds of nibs that are regularly used (notice that most pens only offer a handful of these possibilities!).

EF is a common nib size (extra-fine). A nib that produces a line with a width of about 0.4 millimeters. Suitable for those with very fine handwriting.
F (fine) (fine). A nib that produces a line with a width of about 0.6 millimeters. Appropriate for those with tiny handwriting.
M (medium) (medium). A nib that produces a line with a width of about 0.8 millimeters. Suitable for those whose handwriting is of an average size.
B (broad or bold) (broad or bold). A nib that produces a line with a width of about one millimeter. It is a good choice for those who have huge handwriting or for signatures.
A ("Anfanger" Means beginning). A fountain pen nib with a rounded tip, manufactured by Lamy and designed specifically for the ABC and NEXX fountain pens. However, we are able to adapt this nib to any Lamy pen that utilizes a steel nib. Developed specifically for first-time authors and younger students. In the range between fine and medium in terms of the line width.

Specialist nib sizes

Italic (eg IF, IM, IB, 1.1mm, 1.5mm etc) (eg IF, IM, IB, 1.1mm, 1.5mm etc). A nib that has been honed such that the tip is flat rather than rounded; the nib is often made of steel and does not have a tip. Designed to produce a broad range of line variations, from small side-strokes to wide down-strokes, in the style of a calligraphy pen. Typically, dimensions are given in units of width (in mm). The majority of "italic" nibs that are produced in factories are actually cursive-italics or sometimes stubs (see below), which means that the corners of the nib are rounded to allow for continuous writing. This is in contrast to a proper calligraphy nib, which requires significantly more skill and care to use correctly. The designations MI or IM (medium italic), 1.1mm, 1.5i, etc. are among the most common.
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