From the maker

Setting up a gravity filter usually means tying a knot in cold or dark conditions, then untying it the next morning. The Hang System gets rid of the knot. A PA12 cleat clamps onto 1 yard of 1.8 mm reflective nylon cord: loop the cord around a branch, feed the tag end through the cleat, and the line locks under load. One hand, no knots. Designed around the workflow of a gravity water setup: loop the cord onto your dirty water bladder (CNOC Vecto, Evernew, etc.), which feeds your filter, which feeds your bottle. The whole system weighs 10 g and is rated to about 45 lb. The same 1.8 mm cord is sold by the spool as Reflective Cord; the Carbon Fiber Spool keeps spares organized. Full cord and cleating notes in Rigging That Works.