Review on 🥤 4 Pack 16oz Skinny Tumblers with Lids and Straws - Clear Acrylic, Double Wall, BPA-Free Tumblers - Includes FREE Straw Cleaner & Name Tags! by James Cypert

I have used these massagers several times outside in 90 degree heat. I start by adding ice cubes until the glass is about 75-80% full of ice, and then I top up with cold water from the fridge. The water stays cold for at least 2 hours and the ice cubes are still visible. Even after the glass sat in the convertible for 30 minutes (again in the middle of a 30 degree day) the water was still cold! They are very easy to clean. I wipe down the jar and its lid with a bottle brush (https://www.amazon.com/OXO-Good-Grips-Bottle-Brush/dp/B00004OCLJ) and some dish soap, then run the included straw brush. Put the glasses in a straw at both ends. A quick rinse and the glass is ready for use again.