Looking at the Backpacking Light Bivy Sack Gear Guide (http://www.backpackinglight.com/cgi-bin/backpackinglight/xdpy/ssn/GearDB/pc/Shelters/Bivy%20Sacks/index.html), some bivy bags (e.g., ID BMW) appear to have removable insect netting. Question. How is insect netting attached to the bag? I assume it is a zip-in design, but I would like to confirm.
Thanks.
Chris

