Field Notes bring out special limited editions on a regular basis. Their 60th Quarterly Limited Edition (autumn 2023) was inspired by the birch tree, with the birch's "white, papery bark, evoked here by speckled 110# Mohawk Loop “Snow” cover stock, heavily debossed with just a hint of warm gray" (according to Field Notes). The cover is classically attractive and robust enough to take rough treatment, battered around in a bag or a pocket.
The three-pack of notebooks has other nods to the birch, in the colour of the grid and staples. Birch trees go from green leaves to yellow in autumn, and then the stark white trunks are beloved of black and white photographers everywhere. The notebooks have colour-coordinated green staples with green grid lines, yellow staples with yellow grid lines, and black staples with black grid lines.
As usual, there are 48 pages per notebook, and three notebooks in a pack. The paper is bright white, and the grid-lines are (a very non-metric) 3/16" (4.7mm). The inside of the front cover has space for personal details (including "pertinent coordinates"), and space to indicate if there is or isn't a handsome reward waiting for anyone who finds the book when lost and contacts the owner.
The inside of the back cover has a list of potential practical applications (some of which are weird and wonderful; some of which are just weird), plus details of the specifications of the notebook. It continues with its defiantly imperial measurements by having an inch ruler printed inside the back cover.
I would be lying if I said that the paper inside plays in any way nicely with fountain pens. It doesn't. It plays perfectly well with other pens and pencils, however, and given that this is a pocket notebook, it probably wasn't top of your list for "notebooks I yearn to write in using only a fountain pen."
It's most definitely a limited edition. Once they're gone, they're gone.