The Hydrapak Reservoirs feature a Surge valve with protective cover, 4mm thick thermopolyurethane (TPU) lining with reinforced slider top to match and one-piece
Hydrofusion Insulated Big Bore tube. Because the insulation is applied directly to the tube, it is lighter than standard neoprene insulation which covers the tube
like a sleeve. Available with one, two or three liter capacity.