10PCS Tumbler Shields for Epoxy Tumbler, Silicone Tumbler Protector for Resin Paint,Cup Silicone Insert Paint Spray Shield, Epoxy Resin Cup Protector Clean Rims DIY Glitter Epoxy Tumblers (10)

I get what the purpose is supposed to be to keep the edge clean. I had no success with my 20 oz skinny tumblers. They are too loose and they move around. So I'll continue to use my tapes.

works great, keeps epoxy from overrunning into the inside of cup

These are good for keeping resin from going into the inside of the cup. Has a good stretch and good seal. Love I can spin different sizes without having to wait on a band.

Now this has been a life changer for me. I used to have epoxy and paint within the cups while working on them and gave me a hard time to clean and scrape it off. With these shields I have had 0 difficulty and I love it.

These rings did not fit tightly inside the cups and resign still ran inside the tumbler and had to be cleaned.

What a nightmare! I was so excited about these. I had these pictures of these silicone rings sitting snugly in the tumblers. I saw perfect edges. I did not get that! The rings did fot well, but, the minute I bumped it while putting on resin, the rings came off! I had hands covered in resin. A cup covered in resin. An unprotected interior of a tumbler! I was able to pull the tumbler back and fix it. We’ll see if I kept the resin clean. I doubt it. Let me suggest something way easier!!! Buy liquid latex. I have “Creature Liquid Latex” from here on Amazon. It stinks! It works great. Take your finger, or brush. Dip it in latex, apply to interior of glass, rim. Let it dry. No silicone will stick, and it dries well. When you are done, it peels away cleanly. I suggest you try that route. These are going back. I wanted to love them. I really did!

Love the sizes helps with less clean up, I'm a little messy with epoxy and this helped with my rims.

Haven't used them yet