These are silnylon stuffsacks but rectangular shaped and with a zipper down the middle. They are like a men’s toiletry bag but made with ultralight materials. The nylon is kind of a translucent white which aids in finding stuff inside. Bathtub bottom so you can set it down on a wet surface.
The great thing about this bag is the easy access to the contents by opening the zipper. No more dumping out the contents of your small ditty bag to get at that one item you need that invariably migrates to the bottom of your bag.
The XXS size is the most usefull for the ultralighter. I like to use it as a ditty bag to put all those smaller miscellanous item.
4 out of 5 points due to the heavier weight compared to a lighter stuff sack. The XXS size weighs 1 oz, so about 1/2 oz heavier than an equivalent size silnylon stuff sack but the convenience factor makes the extra 1/2 oz worthwile.