Welcome to- The Fountain Pen Community!

Just picked this one up on eBay:

Complete with two dehydrated refills, one of which I'm attempting to rehydrate. Removing the butt end cap reveals another plug; both cap and plug have a breather hole, as does the pen's barrel. Removing that plug allows one to extract the fibrous breather plug, rather like a cigarette filter, which sits atop a rubber plug with a breather tube through it that reaches all the way to the shoulder near the tip. Removing the tube (not an easy task!) let me add some distilled water with a syringe, and after reassembly the thing is sitting tip-down in hopes that the ink will make its way to the tip.

I gather this type of pen was first introduced by Mitsubishi in 1966, and the packaging and label styles *might* indicate a 1960s pen, but I suspect it was made a bit later. It has a sticker on the package that says it was imported through Yasutomo & Co in San Francisco, but that company doesn't seem to have a Web site or e-mail address I can find.

I'll have to see what, if any, other refills might be made to fit, but I'd like to be able to keep refilling the originals.