The tips can be purchased (Nancy's Notions, etc.)--there 3 in my package. The ones I have are "Folkart, Enamels Tip-Pen" (Craft Tip Set) I see it says the 3 tips are different, one is fine, one super-fine, and one extra-fine.
I see on the back of the package this internet address:
www.plaidonline.com. I have used mine with Elmer's School glue.