This is one of lightest wind breakers we have tested. See the video below for more details. There is also the Tachyon jacket which is a little heavier and comes with a full zipper down the middle and no hood.
We enjoying using this in conjunction with the MontBell EX Light Down Jacket. We can't imagine more wind protection and warmth for under 8 ounces.
We will eventually add this into our complete Wind Breaker Jacket Review.