Of the basic outdoor clothing layers, the insulating layer seems to have had the most advancement and caused the most debate between outdoor athletes. Different activities require different characteristics from the insulating layers that we wear. Skiers need heavy insulation with a durable material and backpackers want the warmest insulation for the least size and weight, but what does the best insulating layer look like for a climber? With stiff competition such as the Arc’terx Atom LT Hoody, Patagonia Nano Air, and the Rab Xenon-X, where does the Mountain Hardware Kor Strata hooded jacket fit this role?
The Kor Strata gets its insulation from PrimaLoft Gold Active. This material is a synthetic insulation that maintains its insulation properties even when it is wet, unlike down insulation. In addition, it is comprised of 45% recycled materials. By all accounts PrimaLoft is a warmer insulation than Arc’terx’s Coreloft insulation and Patagonia’s FullRange insulation and used in the Atom LT and Nano Air, respectively.
This jacket definitely retains the heat that you generate while moving and also blocks out the wind. Even on The Longest Approach in Vermont I was not sweating in this jacket. That approach was about 3 miles, and over 1,000 feet of elevation gain with 30 degree temperatures and 5-10 mph wind.
Because of the way this jacket fits, it does not obstruct climbing either. The material does stretch for full range of motion, and the armpits are given enough material so that the jacket isn’t pulled up the torso if you raise your arms. I am 5’7″ tall and weigh 150 lbs. The Medium fit me perfectly.
With a weight of 14.1 oz, the Kor Strata is one of the lightest insulated jackets due to its simplistic design. The sleeves and hood are are non-adjustable with only an elastic cuff. The hood is big enough to barely fit over a helmet without obstructing the wearer’s view. The waistband is adjustable with a draw at the left hip. This helps to protect from the wind.
There are two hand warmer pockets with zippers and one large chest pocket with a zipper on the outside. This chest pocket is the only pocket accessible with the jacket tucked into the harness. The pocket is a little bit bigger that the two chest pockets on the Nano Air (maybe that’s why they included two chest pockets). I like that this pocket is accessed from the outside of the jacket, unlike the Arc’terx Atom LT and the Rab Xenon-X whose chest pockets are accessed from the inside. That means that you need to open open 2 zippers to get into the chest pocket as well as unzip your jacket halfway. The Kor Strata’s pockets are simple and useful.
The outer shell is rip-stop nylon, which is durable enough to withstand some scraping against rock (unlike the Patagonia Micro Puff) but is also matte and unassuming (unlike the Rab Xenon-X).
The jacket can also be stuffed and stored into its own pocket. The Arc’terx Atom LT Hoody and Patagonia Nano Air do not have this self storing feature, while the Rab Xenon-X does. This is a useful feature for organizing or saving space in your pack.
The main component that we didn’t like about this jacket was the hood. The Kor Strada does come in a version without a hood, however I prefer having something to cover my helmet to protect against the wind and keep me just a little bit warmer when organizing gear on the ground or on a belay ledge. For the most part the hood performed well. With a helmet on, the hood fits perfectly, and does not obstruct sight or hinder head movement. However, when not wearing a helmet the hood is too big and covers the eyes. A quick and simple adjustment like the one for the waistband would make this hood easier to wear and make the jacket a bit more versatile.
Another issue is the zipper looks wavy when zipped up and had looked this way brand new. This does not affect the function of the jacket, but is a detail that may bother some people.
Mountain Hardwear’s Kor Strata Hoody is a an active insulation layer that keeps you warm without overheating. Although it looks similar to other jackets, aspects such as the insulation, shell material, pocket locations, and self storage all add up to make this a great active layer especially for climbers. If you can overlook some minor flaws, this is one of the most versatile and useful active layers on the market.