This is a USED but good condition Gortex, mummy style Bivy cover. They are a #2 grade and may contain some very small holes. This cover goes over your sleeping bag as a moisture barrier. Gortex is a breathable material that lets water pass one way (out) but repels water from the other side, keeping you dry and comfortable. These come in a woodland camo pattern and are ideal for whatever mother nature throws at you while sleeping outside.