These are supposed to be used with the cheap Stypens I just acquired (fun pens, those!)... but I don't know where to order the carts themselves.

They are not the regular 'short' standard internationals. Shaped the same, however smaller overall, as though someone stuck them in a shrinking machine. The converter that came with them is too long with the piston even part-way out to fit the pen.

I tried a couple of internet searches, no results. Any help will be greatly appreciated. Thanks!

Do you mean the standard carts that are say about 1 inch long? If so, I have a few and I purchased mine at Office Depot. hth

No, they don't fit other pens---just the Stypen, apparently. I had never heard of them until I got the Stypens. I'm rolling in the regular standard carts! These, I guess, are the "Mini-me" version of the standard.

Have no idea if this would be any help at all, but..........

Are they the same as the cartridge that Waterman used for the early version of the ICI ET LA small ladies fountain pen?

Sailor, I've got Stypens and they all take the short international version. Ebay is full of them, but any regular B&M bookstore in Europe has them, normally.

Thanks for the tips. However I'm not in Europe.

And I am not familiar with that 'Lady's pen.' All I know is that the converter looks like someone took the regular standard cart and shrunk it in every dimension, not just length. Theoretically the converter should work but with the piston out even a little bit, it is too long to fit the pen.

Just the other day I noticed that some of my cartridges are smaller than the standard size and I remembered your thread. Here's a scan comparing one to a PR cartridge and the long (but skinnier than regular) cartridge that came with my Stypen.
Click to view attachment

I got some of these smaller cartridges for free with my last order from Tryphon (VERY highly recommended shop, very nice people, but am just happy customer, not affiliated). The ink is black and if you'd like to try them I'd be happy to send you some (I mostly use Noodler's Bulletproof Black, so I haven't got much use for them) - just PM me your address.

If you haven't found these yet, I just noticed they are available here.


Zoe

Did you try putting in one of the standard short international cartridges? I've yet to see a Stypen that won't accept them. There are small variances in size between the manufacturers of the std short int carts. But, so small that they all will fit. The only pens that are sometimes tricky that should take these are MB and Waterman. Also, because it gets overlooked all too often and could be the reason the accompanying converter does not fit is because there is a piggy back second cart in the bottom of the barrel .... hard to see sometimes, but you might want to poke something in the barrel to see if there is one lurking.

Sam

Those were my thoughts as well after a careful eye-to-eye comparison. Right now I'm using the one Stypen that can take the long (ie: waterman-type) carts.