With all the weather protection that you need and none of the weight that you don't, this bivy will let you sleep soundly through the night. The 3-layer Gore-Tex Respiration Positive fabric allows you to breathe comfortably while managing condensation and deflecting rain and snow.
Machine wash cold in powder detergent. Drip dry. Or simply wipe with a damp sponge and hang to dry. Always be certain the sack is completely dry before storing it in the stuff sack for any length of time. Mildew will grow on the bivy if it is stored wet.