Traveler - Modern 40 oz Tumbler with Handle & Simple Flip Straw - Car Cup Holder Friendly, Leak Resistant Water Bottle - Reusable Insulated Stainless Steel & Rubber Base

Works well. Very durable. Two lids are a bonus.

Very convenient Leak proof

This is the best tumbler I have every owned. It is extremley well designed. Even the darn straw is designed to be air tight going into the lid. You can put ice it at 9 pm, and the next day the ice is still there and the water is still ice cold. This cups thermal engineering puts others to shame. I own a Yeti, yes they are good, but this cup is even better. You can sit outside on a hot summer day with your ice lasting longer than the water, and no condensation build up at all. Its extremley durable and solid, able to withstand drops without a dent.

As you can see I have the 40oz which is my water cup, I had a Stanley but with two large dogs and being clumsy it got pretty banged up in the four months I had it, but my IronFlask cup has survived all of the same abuse and still looks brand new. My 24oz cup I use for iced coffee or smoothies, and when I say it keeps my drinks COLD it keeps them COLD. I can put ice in my water cup in the morning and most of it will still be there by the end of the day even after refilling. My 20oz is strictly for hot coffee and tea, it keeps it super hot so I usually have to keep the lid off for a few minutes before I seal it up and go. Overall these cups are my favorite of all time. I have used Stanley, Hydroflask, and Yeti but none of them can compare to these cups. I wouldn't say they're 100% leak proof but I definitely have to turn the cups almost upside down for any leakage. Zero scratches, zero dents, the newest cup is my 24oz, oldest is 40oz. I love all the colors but I have to refrain from buying all the cups. The size range is phenomenal compared to Yeti who supposedly has the best sizes (WRONG). And the rubber grip on the bottom is a life saver, I don't have to worry about a tail hitting the cup and it sliding AND tipping over. Overall these cups are solid, reliable, and do not disappoint.

I’ve used many tumblers and insulated bottles but this one wins. Prior to the iron flask my go to tumbler was from Starbucks which was decent for a couple of hours but not so much on the long run. I’ve liked the technology of the mighty mug as a spillproof mechanism, but i still struggled with having the temperature kept in a constant. As a person with bad memory and tends to forget about their drinks quite more than you think, the iron flask actually works well. I haven’t tried it with hot drinks but I imagine it does the job way better than cold drinks, and mind you the first day i got it it kept the ice i had with my drink for over 12 hours. I went to sleep and woke up and legit the ice was there when I checked it.. The insulation technology used is a 10/10. It’s a bit on the heavier side but it gets the job accomplished better than other brands out there. The only downside would probably be the plastic straw. I definitely recommend this for anyone who needs their stuff to be kept at a specific temperature, and anyone who wants their drinks vacuum insulated so it doesn’t spill. Worth every penny and definitely gonna invest in a couple more products from this company.