I may have been wrong and these may fit SKU 1615103 but you may want to ask FT if they fit with this atomizer.

You can ask here if the 2 are compatible General Pre-sale Questions

Just give them the 2 sku numbers and ask if they fit each other. ;)

Does SKU 1615103 glass tank fit with SKU 1682500 T-Protank BCC Clearomizer (2.5ml) T-Protank

Edit: lol you beat me to it JoPatterson

I just remembered protank 2 might fit.