0.66 oz MEMBRANE 10 taffeta nylon
I ordered silnylon, .66oz membrane, and .5oz no-see-um to make a big agnes fly creek clone... it turned out great! Pics are here: imgur.com/a/zMvZHxx
This nylon taffeta membrane is the lightest and highest quality fabric out there. This is the stuff those high end retailers use. A few DIY tricks and you can be making your own quality products without spending the big bucks at a sporting goods store.
Very please with the product so far, I had fair warning that it can be difficult to sew and to use tissue paper as a backing. With this advice, fabrication went smoothly. I made the quilt 6' 6" long and used the entire 58" (minus 1 - 2" for seams) width for my quilt. Not sure if it matters, but I put the shiny side of the material facing the insulation. This material feels very cool and soft to the touch and the color looks just like the pictures on the website. The finished product looks VERY professional, love it. I am taking my hiking quilt on a section hike of the AT next week and will field test the quilt. Quilt weight in at less than 1.5 lbs and I expect it to be good down (pun not intended) to 30 degrees.
I am very pleased with the ease of doing business with Ripstop. They carry good products and are reasonably priced.