Review on 🍵 Insulated Stackable Glassware for Cappuccino Drinking by Joey Gilbert

I bought these 12 ounce double wall tumblers because I needed something to keep my tea hotter longer at work. I liked the way they look on the product page and the 4.5 star ratings gave me confidence despite a number of complaining reviews. When I opened the very well packaged box I was very pleased with how attractive they were without the packaging and they certainly made my first cup of tea even more attractive. When I first used one I noticed that it kept the tea hot. longer, but not as long as some in various reviews claim. And the tea didn't cool down immediately, as some skeptics claimed. Out of curiosity, I decided to test both of the new Kitchables mugs with my favorite 12oz ceramic mug with handle to see how big the difference is. I checked both new cups for consistency. I started by making sure the volume levels are the same. I used a 500ml/16oz Pyrex measuring cup for this and found that all three cups hold 12oz of liquid with about 1/8 the rim. All three cups were tested at ambient temperature and 69 degrees Fahrenheit. I used an infrared thermometer to measure the outside and inside temperature of the cups before filling (an Etekcity Lasergrip 1080 infrared thermometer purchased from Revain). During the test, the cups were placed on identical wooden supports so that the heat exchange at the bottom of the cup was minimal and maximally the same. To take the water temperature I used a mercury thermometer that I've had for a while - faster and more accurate than most instant read thermometers for this type of work. During testing, I held the thermometer in hot water, which was cooling at about the same rate as the cups, to avoid getting heat or cold into the first cup I measured. I started by bringing the water to a full boil. The temperature was 210 degrees (mercury thermometer) when I poured it (212 is hard to get and depends on altitude and barometric pressure). I filled each cup to the 12-ounce mark and measured the outside temperature of the cup with an infrared thermometer. I then checked the water temperature and outside temperature of each cup every 5 minutes for 30 minutes. I found that (as expected) the two double-walled cups measured almost the same throughout the test, so I'll report them as one cup for simplicity. To keep); In a ceramic cup the water was 160 degrees, outside 146 degrees (not comfortable without a handle). 10 minutes: glass cup was 159/107; Ceramic 151/138. 15 minutes: glass cup was 145/102; Ceramic 140/130. 20 minutes: glass cup 141/100; Ceramic 134/122. 25 minutes: glass cup 135/96; Ceramic 125/116. 30 minutes: glass cup was 126/94; Ceramic 120/112. Obviously the double wall cups kept the water warmer longer but after the first 5 minutes they lost about the same heat as the ceramic cups. This may be partly due to the fact that glass mugs had a larger diameter at the top than ceramic mugs (3 inches versus 2.5 inches) and therefore lost more heat due to the larger surface area; Additionally, using coasters could reduce the heat loss of a wide-bottomed ceramic mug (which could happen when using it in real life). Initial heat loss was less with glass beakers, probably due to the fact that double walls can only contain a vacuum as advertised, the thermal conductivity through the solid glass walls of the container is less than through the solid ceramic walls of another beaker. A proper glass lid likely helps glass mugs stay warm longer, just like the lid on a vacuum travel mug. Since I microwave water in a teacup at work, out of curiosity I tested a glass cup by filling it to 12 ounces and microwave it to a visible boil. When measured, the water temperature was only 205 degrees (any physics expert who can explain that can chime in, because I'm curious). However, the outside of the mug has been heated to 125 degrees and is clearly uncomfortable to the touch, likely due to the heat the water draws to the glass as it heats. However, it is evident that the drink stays hot longer simply because the cup itself does not cool it when hot liquid is poured into it. Preheating the cup with hot water before adding the hot beverage will keep the beverage hotter for longer. So what do I take away from all of this? These are attractive mugs, although as others have pointed out they are better for someone with a large hand (like me). They keep the drink warm longer, but not much longer as they are not airtight vacuum flasks or travel mugs. However, if the drink is still warm and not cool to the touch 30 or 40 minutes after pouring, that's a win and these glass tumblers look a lot better than your travel mug of choice. Room-warm water is very convenient, and the guests in my office appreciate a glass rather than a paper cup. Cons: They're difficult to reheat in the microwave because using a hot pad to remove from the microwave isn't safe on smooth glass. For this reason, a silicone heating pad might be better than a cloth, although I haven't tried it yet. Comments on select reviews and complaints: 1. You don't keep your coffee hot for an hour and your coffee cold for an hour. 10 mins. 2. They hold a full 12 ounces with room for a sip. 3. They are not very fragile. However, if you drop or forcefully flick the glass on the floor or table, it may break. I've had glasses that crumble in my hands just touching them together and glasses are hard. Would I buy them again or recommend them to friends? Yes. While they don't keep my tea hot for as long as a ridiculously expensive branded travel mug of your choice, they are also very nice to look at and hold.