Hand wash only recommended. Most likely this is a vent at the bottom of the cup. Sealed but the dishwasher temperature can open it. But I don't know if that's why they offer hand washing. Sounds like glass when hit with another cup. Works well with limited condensation on glass. Nearly nothing!
🍿 Revive Your Carnival Experience with Popcorn Nostalgic Accessories and Supplies!
7 Review
🍿 Enhance Your Popcorn Experience with Flavacol Popcorn Season Salt Carton
7 Review
🎪 Nostalgic Fashioned Carnivals Fundraisers with Resistance Twist
5 Review
Premium Carnival King Paper Popcorn Ounce - Unrivaled Quality & Taste!
7 Review