BYO by BUILT 30 Ounce Double Walled Stainless Steel Tumbler Gunmetal 5197080

This vacuum bottle has a relatively small diameter lower section and larger diameter upper section to hold a whopping 30 ounces of liquid. It is made of 18/8 stainless steel which means it is made of 18% chromium and 8% nickel, same as used in high end stainless tableware. It is extremely unlikely to stain or rust and the nickel makes it very strong. Often people don’t realize vacuum bottle is the generic term of a trademarked product called Thermos™ Bottle. This Built in NY container is 8¼ inches tall and just a little under 3 inches in diameter at the bottom and just under 4 inches in diameter at the top. It holds a 30 ounces of liquid. That’s just a little less than 4 measured cups of water, not a coffee size mug. Most coffee mugs hold upwards to two cups of water, so think of it as almost two coffee mugs. Oh, be sure to scroll down to see my temperature test chart.This vacuum bottle fits in the cup holder in the center console of my late model Honda Accord quite easily – probably an industry standard size. Look at my photos so you get an idea how it fits. This vacuum bottle has a sliding rotating top to open access to a small opening that a flexible plastic straw can pass through. However, a common straw would just fall completely inside. You’d need an extra long one. I have some long glass straws that can almost fit through the opening. However, even though the glass straws are longer, it would probably slide and fall inside as well. So the only viable method is using your lips and the age old technique of drinking from a tall bottle or glass.You might find an extra long straw the next time you go to your favorite fast food restaurant. Perhaps recycle it by taking it to your car instead of throwing it into the trash. I wouldn’t recommend drinking coffee through a plastic straw, however – hot liquids can possibly leach undesirable chemicals out of the plastic and into your mouth. Glass or stainless steel is safer from a chemical standpoint. Naturally, glass is breakable as evidenced by a 55 year old scar still visible in the palm of my right hand from chemistry class.The following chart will give you some idea of its ability to keep the contents cool. I keep my refrigerator at 38° F and keep a lot of bottled water inside. I put this vacuum bottle in the deep freezer at -8° F overnight, so this contributed to a slightly better start, but longer term, it didn’t contribute much for very long. You will notice that the warmer the water becomes, the less the temperature changes per hour. That is because the water is getting closer to the outside room temperature of 75°. So there is less temperature difference between inside the bottle and the outside. Therefore there is less temperature differential between inside and outside. Eventually the inside and outside temperature will become virtually the same – given enough time.Starting Temperature: 37.7 degrees F.44.6° after 3 hours…..… Gain of 6.9° - not bad considering a plastic lid48.7° after 5 hours…..… Gain of 11.0° Overall50.5° after 7 hours…….. Gain of 12.8° Overall55.2° after 9 hours…..… Gain of 17.5° Overall58.4° after 12 hours…… Gain of 20.7° Overall64.0° after 20 hours…… Gain of 26.3° OverallI haven’t tried this vacuum bottle with coffee because I’m not much of a coffee drinker, but I do like to sip ice cold water in my car for even relatively short trips. So I did a temperature test to test how well it keep the water cool. The test was done with an ambient temperature of about 75 to 76 degrees in my house, so that is a fairly benign temperature environment. What I learned is I will need to add some ice cubes to keep the water temperature low enough for my preference for ice cold water.Now if you are starting off with very hot coffee, the temperature change will be faster than the chart above would indicate – because the coffee temperature compared to the room or ambient temperature will normally be much greater. Unless you are storing this vacuum bottle in a hot car in August, that would be the case. The rate of temperature change is a direct correlation between the inside and outside temperature difference. The greater the temperature difference, the faster it will heat up or cool off the liquid inside. It’s just physics. The bottle materials and overall construction do have some to do with how fast this occurs, but these days, the concepts are well understood and there’s not a huge difference in thermal design.Lid designs do have an impact on thermal gain or loss. A true vacuum bottle usually has an insulated stopper that protrudes into the bottle. But this Built NY lid is quite clever. In a way, it is double insulated by creating a small air gap by way of the slider that snaps into the center of the lower part that seals against the opening of the vacuum bottle. Furthermore, it doubles as a way to greatly reduce leakage if you tip it over – if you grab it in time. However, no matter how fast you are, it will spill some liquid – just a matter of how much. They left an air gap so air can get inside as you drink the liquid to make it easy to gulp your drink faster. To make it easy to clean, you just unsnap the lower center by pressing on it and you get two easy to clean plastic disks.

So far, I love this mug. I needed a big insulated tumbler to help me to stay hydrated better. I love that in the hot weather, I can toss some ice in it and my water will stay cold for a few hours even with the ice melted. Now that it's getting colder, I plan on adding warmer to hot water to help keep me warm especially when I'm working outdoor markets. I also prefer drinking from a straw so it's not leak proof as long as I am using a straw. But I do like how the lid can be separated into two pieces which makes cleaning so much easier. It also fits in my car cup holder perfectly. I'm assuming cup holders in cars are standard no matter what the make and model. Overall, it's a win for me :)

Not leakproof otherwise a good beverage container

Keeps liquids nice and cold for hours. I have not used it for hot liquids. I like that you get an extra lid and the straws. Cheaper than the other brands. I like the colors. Doesn't leak. Would purchase again.

Love it !!

Great cup to use at work for water

Easy to hold, keeps hot liquids hit and cold liquids cold. Missing replacement lid in original order but built sent one out immediately. Top notch customer service

Insulated stainless steel giant-size beverage mugs are the new must-have gadget (of 2017). A variety of different shapes and styles are appearing everywhere. Are they all the same? What should you look for?Well, no they are not all the same as much as they may look like it. First off how much. The “original” mug is around fifty bucks but often can be had for a bit less. It has a slight barrel-like shape but is essentially the same diameter from top to bottom. If it fits your vehicle cup holder you’re good but if not, there isn’t much you can do about it. The one I own is the rtic which a best seller. It is at the low-end of the scale but is virtually identical in terms of performance to the fancier model. It has the advantage that the lower half is tapered down to a smaller diameter so it can fit into small cup holders and suspend itself into the open-ended style of cup holder. There is another similar model in which the difference between the top and bottom diameter is squared off rather than tapered but I find that style very difficult to hold. Once you have one of these and fill it with liquid you will understand that the wider top half gets heavier than the bottom, so where the cup is tapered and how much it is tapered makes a big difference in being able to balance the cup comfortably.Now getting to this new model. At first it is virtually identical to the best-selling one but after using it recently for a 3000 mile road trip I can see some definite differences (besides the obvious at checkout). Of course the most noticeable thing is the mint green color. Yea! At least I don’t look like 100 other people walking down the street with their shiny 30oz stainless steel insulated mug. The mint color is beautiful.There are some subtle things though, like the fact that the line where the cup becomes wider is slightly higher than the rtic. I found that it made the mug a little more top-heavy and more prone to fall out of the cup holder in one of my vehicles, unfortunately the bumpier-riding pickup truck. The mint version also has a clear plastic slider to cover the opening where you sip the beverage. I don’t care for it. First off, coffee gets under the two pieces and gets sticky making the slider hard to operate. It is also a chore to clean. But worse, those trapped drops of coffee have the worst tendency to dribble out just when I am wearing a clean white shirt. I don’t think a sliding cover is necessary but if that’s your preference they need to redesign it to make it work better.The thing I like least about this version, though, is the fact that there is an open weld seam that runs the entire length of the inside of the mug. It’s the only model I’ve seen with that; the rtic for example is one continuous piece of stainless steel. I’m not a fan of places that stuff can gather and have to be cleaned.What about the 8 hour claim? This mug (like the entire category from anyone) does do a substantially better job at keeping beverages hot (or cold) than any plastic mug I’ve ever seen. I was driving through some areas where the temperature was 25 degrees and starting with a hot cup of coffee it was still hot enough to burn my lips 2-3 hours later. By 6 hours the coffee was still drinkable but by 8 hours, sorry, it wasn’t cold but it wasn’t much fun to drink. I don’t consider than a negative for this brand because they are all made essentially the same and their performance will all likely be similar.The conclusion is that this one is out of range, but since cool colors are usually more I won’t take anything away for that. The lid design is a personal preference but I personally don’t like it. But I can’t ignore the open weld seam inside the mug … that shouldn’t be, and I can’t consider this a 5-star product because of it.

It’s gorgeous there’s no two ways about it, the lid mechanism is aesthetically pleasing and nifty and it keeps my drink hot for hours even when the drinking part is open!This is for work when I quite often leave my drink and only get to come back to it when it’s stone cold so it’s going to be great for that.The only problem I have is that it doesn’t fit in the cup holder in my car :( it’s too big (Renault Megane).I like it though, I use it around the home too when I’m busy and don’t want my cuppa to go cold whilst I’m otherwise occupied.One thing to note would be let it cool before you put the lid on otherwise it’s going to stay far too hot to drink for quite some time! I left the lid off mine for five mins and it stayed hot for over four hours (with the sippy bit open!)Anyway, nice product and if you don’t need it to fit the cup holder in your car...buy it!Easy to take the lid apart to clean, push the clips in underneath and out it pops. Wash by hand only.Edit: doesn’t seem to keep cold drinks cold for as long as hot stuff stays hot.* IT IS NOT DESIGNED TO BE LEAKPROOF *

Love the colour. Tbh that was the main reason I purchased it. If using this in winter, make sure you wear gloves as it's metal and bloody cold to hold when outside! On the plus side, it keeps your drink warm for a few hours. Be careful when washing the lid - the rubber thing is what keeps the travel mug closed and I understand from the other reviews you can't just buy a new lid separately. Also, when you drink tea sometimes it spills into the double lid and you can't get it out until you wash it so if you have OCD you'll probably spend your morning commute trying to clean the lid and then giving up until you get into the office. Oh, also it scratches kinda easily.

Seems to be good quality. Easy to clean cup, lid a bit more difficult. As has been said lid is not leak proof. Holds the heat very well, even without the lid.Flavour wise not quite as good a china cup in the shop but does compensate by keeping the drink warmer.Good way to earn extra stars at costa for using your own mug. Overall does the job well at a good price.

The lid is made from 3 parts which is all separable and makes it easy enough to clean the whole thing properly. It holds the temperature of my coffee for hours which is great and annoying in one time (in case you want to drink it straight away as it doesn't get cool for literally hours, but then if I forget about my coffee, which I do quite often, it's still warm just like fresh made). Leak proof - well if you keep it straight in your hand, then yes. I guess you're not gonna put it in your bag right? I'm very happy with my cup.

I have two of these tumblers in mint green and pale blue, both of which look great. The lids are not built to be leak proof as they are made of two overlapping pieces of plastic. The top part of the lid separates from the bottom layer, making them easier to clean. Both tumblers were received quickly and without any damage.