This vest is ideal as a midlayer for backpacking. When it first arrived, I was shocked at how thin it was. I initially concluded that it was much too thin to be of any use at all. I was completely wrong about that. As with all loft-based insulation, it will take some time for the insulative properties of this vest to increase to their maximum efficacy. I'd estimate 5-30 minutes will be necessary, depending on your output level. After wearing this for an hour while outdoors in 40 degree weather, I put my hand on my base layer, just below the vest, and then on top of the vest, under my top layer. The difference in temperature between the inside and outside of the vest was shockingly large. I have no idea how a vest with such a small amount of loft can be this insulative, but it is. Being so thin, this vest is ideal for backpacking, as it can be packed into a tiny volume of space. While the polyamide fibers are, apparently, naturally hydrophobic, I'd recommend using this as a mid with a good shell, as should always be the case for any correct layering scheme. I would estimate the insulative properties of this vest to be in excess of, or at least equal to, Polartec thermal pro with far lest bulk.That being said, this vest is quite expensive. If you are just going for a walk, you probably don't need this. If you are backpacking at temps around 30-40 degrees, or down to perhaps 20 overnight, this is an excellent choice. You might even been able to leave your zero rated mummy bag at home if you have this with you, and pack your 30 degree bag in it's place. This vest really is just that good.Additionally, I strongly suggest wearing this directly above your base layer. That will allow it to maximize the thermal differential. You could wear this as such:Base layer - polypropylene, preferably, but that's a personal choice. But literally nothing insulates better than polypro.Low mid: vestHigh mid: Fleece in whatever weight you prefer. Or wool, of course.Shell: Good old Gore-tex ('cause I'm old school and nothing works better, IMHO.)That combination should be sufficient down to 20 degrees, depending on the weight of your fleece layer - probably would need Polartec 300 for that. That's very impressive with just 4 thin layers. No giant ski jacket needed ;)It wouldn't be safe to do that if this vest was not so outrageously insulative.Great fit, light, and perfect for wearing over a tee shirt on cold morning. HH quality. I am a ski instructor and will likely use it as a base layer. Large pockets will be handy. I have the blue camo version. The look and color are like the ocean. Provides a conservative homogeneous look rather than a typical hunting or camo look from a distance.I bought it for a friend. He loves this vest very much. Warm and comfortable, in sizeYou really can’t go wrong with an H/H product. This one is light weight, fits true to size and overall quality is excellent. My son loves it!Bought 2 of these great item! True to sizeFits and looks great. Always satisfied with my Helly purchasesVery lightweight and packable, was perfect for hiking in the woods in Alaska.Love the weight and thickness. Very very lite and very very warm.Super warm non bulkyPedí la talla M y es de un tamaño descomunal. Lo devolví.Muy contenta, buen producto y de calidad.Hammer Weste ... passt wie sie soll und spitzen Qualität ??I was asked if I’d like to review the Helly Hansen Men's Lifaloft Lightweight Insulator' Vest, Charcoal Camo, L, and I said yes.The body warmer is well made and the stitching is finished off properly.It’s made from water resistant and windproof fabric, which has LIFALOFT insulation, (which is based on a yarn technology that traps more air vs polyester at a lighter weight). You’ll find this has dual YKK zipped hand pockets.It was raining today, so I was able to test if it was waterproof, and the answer is “Yes, it is.”This fits nicely, is very comfortable to wear, and looks well when on.It’s great for both Autumn and Spring days, when you’ve fine chilly weather and you can wear it on top of a sweatshirt or polo shirt.I’m really pleased with this body warmer.