Extremely lightweight and roomy sleep sack or sleeping bag liner for hotels, youth hostels, alpine huts, boats, planes and trains.High quality silk is the optimum fabric for minimizing packing size and weight. Silk is breathable, soft to your skin and responds well to changing temperatures. It keeps you cool in the tropics and toasty in the mountains. Hand or machine wash (gentle cycle) with mild detergent or dry clean. Do not bleach or use stain remover. Wash separately. Rinse in cool water and add a little vinegar to maintain shining colors. Drip or tumble dry low. Do not wring.