Review on Sun's Tea Double Walled Drinking Glass, Manhattan-Style Glass - Ideal for Hot and Cold Liquids, Whiskey, Bourbon, Vodka, and Scotch - Premium Borosilicate Clear Glass - Set of 2 by Mike Ken

These jars have received nothing but compliments and interest from all the friends and family who have had the pleasure of seeing and using them. According to the product information, air is an excellent insulator. When I make cocktails and pour them into these glasses with a large ice cube, the drink stays cold on average 15 minutes longer than if I pour the same cocktail and large ice cube into a regular glass. *minor niggle*: The only downside is that the large ice mold I use creates cubes that are barely too big to fit in a glass when the cube mold is more than 90% full of water before freezing . Water expands when it freezes, making it slightly larger than a hole in a glass. This is solved by running room temperature cold water over the corners of the cube for about a second, making this a very minor inconvenience (not even deserving of one star) and worth it for anyone who cares used for the same purpose of being mentioned.