This vest has been a great find, so far. It arrived packaged in a case with a lingerie bag for washing and the boxed USB-C Battery. The battery slips neatly into a designated pocket near the left hip and is unnoticeable. There are two zippered hand pockets on this vest so you can keep your hands warm or stash a few things without having to worry about having them fall out.The USB connection has a protective cap attached to cover the USB cable when washing or not connected to the battery. The battery is charged using a USB-C cable, but the power cable for the electric heat in the vest is a USB-A connector. The vest can be used with any USB-A 3A power bank, and I was able to fit a larger one into the battery pocket with no problem.The power switch is an LED illuminated button positioned above the left-hand pocket.The vest has a nylon shell and soft polyester filling that adds warmth and comfort without turning on the electric heat!There are three heat settings and 7 heating elements distributed across the chest, back, and neck. The heat is turned on and the settings are changed by tapping the power button. The battery lasts longer on a lower heat setting.So far, this is a great vest for what I needed which is to stay warm in drafty indoor environments. I wanted a vest that had the battery included and costs less than $100. I had no plans to use this outdoors (but I did try that last weekend!). Indoors, I can wear it on the low setting and it keeps me toasty for hours. Medium and High settings are too warm. Outdoors, it needs to be worn under another jacket to keep the heat in. On High setting without a jacket over, I was having trouble staying comfortable in 40 degree (F) weather. With a light jacket over the vest, the Medium setting worked really well in the 40 degree (F) temps.Based on all the options that are available on Amazon, this vest is manufactured inexpensively in China. I do not have high expectations for it, as I saw many similar comments in product reviews where customers encountered problems.So far this vest works well. This is a Men's XL and the zipper IS installed in reverse so the pull is on the left side instead of the right. I think the fit is pretty good. I wear large and XL shirts and this is slightly loose, but not so much that I cannot feel the heat. The cut across the shoulders and arm holes feels a little different from other vests I own. None of these issues would prevent me from buying it again.Some Notes: on a couple of occasions the heat setting seemed to have unknowingly changed. I think the power button is sensitive enough that I may have inadvertently pressed it while moving around and wearing a jacket over the vest! The power indicator stayed on 3/4 lights after wearing the vest indoors for several hours, Last weekend, when wearing it outdoor for several hours, it suddenly stopped working and the power indicator dropped to 1/4 lights. I don't know if this was because I had it on a higher setting, or if the power indicator goes from 4/5 to 1/5 quickly. Stay tuned...Also, this vest does not have independent heat zones. All heating elements are on or off. I noticed some other vests that allowed the user to only turn on some heating elements. I didn't care about this feature so it wasn't important to me.I would highly recommend this vest, especially for Platelet/Plasma pheresis donors, or infusion patients. Since a few customer reviews complained that the vest stopped working or the battery stopped charging after a few uses, I will attempt to update the review if something changes.I'm 5'7" and 195 lbs. I normally wear a Large vest, though it has gotten almost a bit tight ever since having gained 20 lbs during the past year while under the COVID-19 quarantine. With that said, I had ordered the LARGE vest, and when it arrived, it said "MEDIUM". I thought that was a shipping error, but as it turned out, in one of the product pictures, it clearly states that LARGE (USA) is equivalent to MEDIUM (Asia). The irony did not escape me that I'm actually Asian, but I digress.I returned the original vest and got an XL (USA) which is equivalent to 2XL in Asia. That one fits me perfectly.With sizing taken care of, there is a battery included in the left-side, zippered, inner pocket. It connects to a detachable USB cable. The heating element is activated by long-pressing the power button found on the exterior, upper, left chest. It'll fist turn a slow-blinking red, starting it in Automatic mode. After a while, it'd switch to Blue (Low heat), or you can press the Power button to immediately go to Blue. Push the same button to cycle through as follows:- Initial Long-press > Slow-blinking Red: Automatic (which later turns Blue)- Blue: Medium heat- Green: Low heat- Red (Solid): High heatLong-press again to turn off.You can immediately feel the heat building up around the neck... it felt really good. It eventually heated up the chest, upper & lower back, and abs too.My biggest concern about this jacket is whether the heating element is safe and would catch on fire. The product description claims CE certification and to be safe. I certainly hope so. I have been wearing the vest for 4 nights now (unzipped in case it does catch fire so I could get out quickly), and so far, it appears to be quite safe. Only time will tell, and I hope I'd never have to find out otherwise.The battery supposedly lasts between 3-10 hours, depending on which heating mode you select. You can extend this with extra or higher-capacity batteries.The vest itself -- even without the heater turned on -- is quite warm and looks great. As long as the vest continues to operate safely, this is one of those "life changing" products to take camping/boondocking.This is a great vest but the zipper broke so can no longer use and the cost is too much to replace. It would be nice if the zipper was the same quality as the rest of the item.I would buy cheap ones thinking what could be the difference. But the battery cables would break or the buttons would stop working. This is a very nice jacket it feels high quality. Unlike cheaper jackets the warmth is full through the jacket as opposed to feeling hot spots. The neck portion doesn't get too hot to make your neck uncomfortable like the cheaper jacket I had. Maybe one of the greatest things is the battery cable has a material shell. Many of these types of jackets will fail because the battery cable will break. This battery cable is incredibly flexible. The only negative is the pocket where the battery goes in has a very cheap fragile zipper. When you wear it under a jacket it heats up quickly and floods you with a blanket of warmth. Very nice very happyThis heated vest has been a God sent for my nephew. He works outdoors and has a few hobbies outdoors so the cold is kind of hard to avoid for him. I ordered this vest as a gift for him for Christmas and he told me he uses it often. Thankfully this vest came with a rechargeable battery pack so I didn't have to purchase anything extra. As soon as you power the vest on with just a few seconds you can feel the vest starting to warm up. He told me there were times where he was freezing so he turned the vest on and within 20-30 minutes he had to take off a few layers cause he was sweating. This vest feels very natural on, it is lightweight yet very warm and you do not feel the pulling of wires or anything uncomfortable. There is a small inside pocket which is where you store the battery pack. He has been using it now for a few months and loves it!