Simply press and release and your ready to GO!! Spring loaded Piston filler New take on affordable fountain pens Comes in EF, F, M, B, Stub1.1 nib sizes. Please look at other listings for different size

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?)