Review on ☕ BTaT- Insulated Coffee Mug Set of 4 - Large 16oz Double Wall Glass Cups for Coffee, Tea, and Lattes by Jermaine Shuster

09/26/2020: I bought these mugs in April 2020, so just over 5 months ago. We've been happy with them - they're delicate, but we've always treated them with TLC. Unfortunately I took one out of the dishwasher this morning and there was moisture inside the mug itself. You may have experienced something similar with a double glazed window where the seal fails - moisture gets trapped between the two panes of glass and cannot be cleaned . There is a small hole/hole at the bottom of these mugs which must be related to the manufacturing process. Unfortunately this mug lost its seal and now there is a tiny hole between the two sides of the mug that allows moisture to seep in. . You see a cup with an open hole and another with a seal. I thought the seal was originally glass but now I'm thinking it might be silicone. I love these mugs so I'm very disappointed that they have this design flaw. Because of this reliability issue I have to give them 1 star. Update: 01/10/2021 Three more cups failed in the same way. I've just switched to another brand (Bodum) as I really like the double wall design but not the reliability issue with that manufacturer. Bodum claims to have invented this type of mug in 2002, I have not done any research to verify this claim. Bodooms are sealed differently below, I've added a photo to show their approach. Hopefully it will become more reliable over time.