
T-Mobile’s latest Tuesdays free perk is perhaps one of the most useful: a water bottle! You can take it to the gym and keep your cold water with you at all times. It’s not insulated or anything like what you’d get from brands like Owala, but it gets the job done well.
And it will continue getting the job done… just so long as you don’t leave it in your car during the very hot summer heat.
We’ve now seen at least two instances so far of people who have left T-Mobile’s new free bottle in their cars, just to find hours later that the bottle had just melted and shrunk in size. Allegedly, the bottles themselves are made with 100% recycled PET plastic, which is typically what you can find in regular water and soda bottles, as well as some low-cost reusable water bottles.

These are sensitive to heat, and as you’ve probably noticed, it’s very hot outside right now. If you come back to your car after leaving it parked in the sun for hours, there is a non-zero chance that you’ll find that it has melted. Even if it didn’t melt, the bottle might still chemically break down slightly, passing chemicals into its contents.
Keep in mind that PET bottles actually melting and shrinking inside cars is actually a pretty rare scenario—it’s something that happens way more often in the dishwasher (which, by the way, this bottle is not dishwasher safe). So the fact that it didn’t just happen once, but it already happened twice, and on day one of this promotion, says a lot. Either it’s *very* hot outside (it is!) or these bottles are especially low-quality. Or both.
If you claimed a free bottle and you plan to use it, let this serve as a warning that you might not want to leave it in your car, at least if you’re going to leave it parked for a long time. And if you already did, and it didn’t melt, you might still want to replace the water inside. Just in case.