The concept of zoned insulation is nothing new. A number of brands have created jackets that combine both down and synthetic areas of insulation, some include different, breathable fabrics to create the zoning instead. This is most commonly done with lighter, more breathable fabrics under the arms and down the sides of jackets with the majority of the warmth covering the core. Rab's new Kaon jacket takes this zoned insulation concept to the next level with the use of 800FP hydrophobic down, their own proprietary Stratus synthetic insulation and highly breathable Pertex Quantum Air fabric too.
Rab Describe the Kaon as:
Designed for alpinists looking to do more but take less, the Kaon Jacket combines intelligent zoning and breathable inserts to offer warmth and protection without the weight penalty.
Conceived as the next step in insulated layers, the Kaon Jacket employs a combination of high-loft hydrophobic down, quick-drying synthetic fill and insulation-free underarm sections for the ideal balance of warmth, protection and movement. Its intelligent zoning of materials uses 800 fill power European goose down in the body, quick-drying Stratus™ insulation in the cuffs, shoulders and hips and Pertex Quantum Air panels under the arms, ensuring that warmth and flexibility are matched by outstanding breathability when your climb gets intense. Built using Atmos™ lightweight ripstop nylon, the Kaon Jacket uses a half-hem drawcord and elasticated cuffs for a close fit, alongside a YKK front zip and features a chest pocket for storing essentials.
With stitch-through construction and a handy stuff sack for easy packability, you can enjoy the core warmth, active dryness and multi-application versatility of the slim-fit Kaon Jacket, wherever your path leads.
Down is still the number one insulating material in the outdoor industry, offering the lightest warmth to weight ratio and unrivaled packability. Therefore, a down jacket will provide exceptional warmth but won't weigh you or your pack down. It excels in cold, dry conditions. However, with technological advances in recent years there are synthetic options for insulation that have improved greatly in terms of mimicking the performance & properties of down.
When a jacket utilises down in certain zones these are usually areas which are considered to need the most effective insulation such as around the core of your body and along the tops of your arms. Areas that are more likely to be compressed such as under your arms and down the side of your torso will negate the insulation of down which needs to loft to provide warmth, so in these areas it is more useful to utilise synthetic insulation or breathable fleece and softshell fabrics.
The Kaon uses 70g of high quality, 800FP hydrophobic down (65g in the women's jacket), providing incredible warmth and added protection against moisture damage. The jacket uses a stitch-through construction with a high number of small baffles to ensure the down doesn't migrate around the jacket providing maximum coverage. All of Rab's down is RDS Certified.
Synthetic insulation is effective at keeping you warm whilst dealing with moisture, especially when compared to down. When synthetic insulation is soaked through there's very little drop in insulating performance and it will offer vastly more warmth than down, making it the perfect choice for damp and cold conditions, which typical of Scottish winter climbing. Synthetic insulation is also easier to clean and care for.
For a jacket with zoned insulation, synthetic insulation provides durable and reliable warmth in areas that may see the most abuse. Across the shoulders in the area where rucksack straps will sit is a perfect example. If this area was insulated with down, the down would be compressed by the straps, giving little to no insulation and it may also become damaged over time. Synthetic insulation is very durable and wouldn't be damaged from wearing rucksack straps. It also has a much lower volume over a jacket insulated with down making it more effective at insulating when being compressed.
In the Kaon, Rab have used their own proprietary insulation Stratus. Rab says that they have found Stratus to be 20% less absorptive compared to rival insulation such as that from PrimaLoft. This helps the jacket breathe more and dry out faster. The Stratus insulation is also made from 100% recycled materials.
The Kaon uses different fabrics to create a weather resistant yet breathable jacket. The use of the slick and highly wind-resistant Atmos outer shell, minimises down leakage while still allowing enough room for lofting. This results in an impressive level warmth retention despite its very light weight. With the Atmos fabric Rab have managed to minimise both the weight and cost effectively.
For extended areas under the arms, Rab have used the highly breathable Pertex Quantum Air fabric. The more openly woven structure of Quantum Air allows airflow through the fabric, which helps to regulate your body heat and keep you comfortable for longer. This balance of air permeability and wind resistance means Pertex Quantum Air fabrics are perfectly suited to intense mountain pursuits.