As far as I know this is the lightest stretch woven jacket on the market.
I would have killed to have this windshirt in Patagonia. The constant flapping of my loose fitting 3 oz winshirt nearly drove me crazy.
A stretch windshirt can fit closer to the body without restricting movement. In addition, the fabric itself is quieter and less prone to flapping. A light stretch winshirt is ideal for activates like x-country skiing, biking, where you don’t want flapping fabric to slow you down or for climbing where you want a trim garment to stay out of the way.
MontBell's Stretch Ballistic fabric on the Stretch Wind Jacket should have better breathability than the slightly canlendared ballistic nylon used on their lighter winshirts without compromising abrasion resistance. Offering an excellent blend of breathability and wind/rain protection, this is the jacket for cool weather endurance activities. The DWR and naturally water shedding properties of a woven fabric should provide reasonable water resistance making the Strech Jacket a very light softshell indeed.
Polkatex DWR treatment
One chest pocket with concealed zipper
Weight (men's): 5.6 oz
Weight (women's): 4.6 oz
"Montbell Stretch Wind Jacket (Outdoor Retailer Summer Market 2005)," by Alan Dixon. BackpackingLight.com (ISSN 1537-0364). http://backpackinglight.com/cgi-bin/backpackinglight/mont_bell_stretch_wind_jacket_orsm05.html, 2005-08-14 03:00:00-06.