I hope all is well. For yourself and others that may not already know, I wanted to shed some light on the relationship between lightweight fabrics and down jackets.
Lightweight fabrics allow companies to create jackets that weigh less and pack smaller. This is because it lets them use higher quality down with a higher Fill Powers. Higher Fill Power means you need less down to keep you warm, as long as the down can still loft to its full potential. A tougher face fabric will be heavier and limits the down’s ability to loft, undoing all the work of creating a jacket that takes up less space and weight in your pack when not in use. If you are in a situation where you might tear your jacket, you can always throw a shell jacket on over the top to protect it.
The outer fabric of this jacket in particular is made from Pertex Quantum Pro, which is a 20D Nylon ripstop fabric. It is durable for its weight/thickness and thanks to the ripstop construction, if you do manage to tear it then the tear won't spread. A quick patch up with a bit of black Gaffer tape will have you back on the road in no time until you are able to get a more permanent repair done by Rab, which you can talk to us about if you ever need to.
This is currently the first ever batch of this military specced Neutrino Pro jackets and the market research showed that the most appropriate colour to produce for this first run was black. However, other colour option might be considered in future product runs, but this is dependant on the overall success in sales of the jacket and on feedback pointing towards other colour options.
This is because they are designed for completely different environments. The Kosa 3 MKII is mainly synthetic (90% synthetic/10% Down). This would make it great for the typical damp UK climate and would be great when you are moving.
The Rab Neutrino Pro Military uses 100% goose down that has been Hydrophobically treated to resist moisture. It will also be a lot warmer compared to the Kosa 3 MKII and is more suited towards static situations in cold dry environments in places like Scandinavia and in the Arctic Circle.