So I posted this a few days ago on instagram but I figure I'd bring it here in case anyone might be interested.
Forever ago I bought a cheap calligraphy pen. I think the actual pen itself was a cheap plastic and liked to leak ink out, and I didn't use it often, so it was unused and I lost it sometime between now and when I bought it.
That was the Hero 5028 PolyPack from ebay(comes with 1.1, 1.5, and 1.9 stub calligraphy nibs)
Now, the Jinhao 992 fits the replacement nibs. It took some wiggling to get them out of the old nib units but they fit like a glove into the Jinhao 992's, no wiggling, no extra space, perfect swap.
They write great in the 992 body, too.
Still haven't found a Medium or Bold nib that fits into the Jinhao 992, but the Hero 5028 polypacks are currently $4.99 on ebay, meaning you can get 3 replacement nibs for the Jinhao for $5
Has anyone found a Medium or Bold nib option for the Jinhao 992?