The famous TWSBI Vac700r is now pocket sized!

Simply pull up, push down and your ink is filled, ready to go. 

Vacuum filler type fountain pen. 

Also designed with a ink shut off valve for easy carry and no mess on airplanes.
Cap can screw onto the back of the pen even with the valve open.

Comes in EF, F, M, B, Stub1.1, nib sizes (please choose one)

Please note: Ink is NOT included

A quick no brainer guide in choosing nib sizes in an overly complicated fountain pen world:

If you write small, go with an EF
For the normal writer, F is the most popular
If you tend to lean on a bigger font, M will be perfect
B is for statements!! Sign a check in B, write a header in B, do some coloring/shading in B
Stub nibs are italic in writing style (have a special card or invitation to write?)