TWSBI Diamond 580 Replacement Nib

This stainless steel replacement nib unit fits the TWSBI Diamond 580, 580 AL, and 580 ALR. It's also backwards compatible with the 530 and 540. It includes the nib, feed, housing, and clear grip section.

Choice: EF, F, M, B, Stub1.1 and Stub1.5

Will fit the previous generation 540 and 530 fountain pens. 

Easy holder case for storage when not in use. 

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?

For more pens from TWSBI; https://www.stickerrificstore.com/collections/twsbi