Aqua M3 Duo Bivvy

Aqua M3 Duo® The ultimate in spacious comfort, offering luxurious 2 man capacity with the same great features as our top selling M3 Armo making the M3 Duo the most feature packed 2 man shelter available. Offering superb ventilation, thanks to its front and rear mozzi vents, perfect for summer sessions on the continent while an extended wrap available separately will keep condensation at bay on those cooler winter sessions. The Aquatexx used for this product has reached a hydrostatic head of over 14000mm/H20 (mbar) in tests by an independent testing laboratory. What does Hydrostatic Head mean? In simple terms it is an accurate measurement of the water repellency of a material. Rain resistance is measured as a hydrostatic head in millimetres (mm). This indicates the pressure of water needed to penetrate a fabric. This is simulated, in a simple way by placing a tube onto a piece of the fabric to be rated. Water is steadily added until it forces its way through the material. Just before it penetrates the material is the hydrostatic head measurement. There are lots of factors that affect the Hydrostatic Head, heavy or wind-driven rain has a higher pressure than light rain, standing on a groundsheet increases the pressure on any water underneath, and the pressure of rucksack straps on a jacket increases the pressure on the shoulders and so on... Fabric with a hydrostatic head of 1000 mm or less is best regarded as shower resistant, with 1500 mm being usually suitable for summer camping. Tents for year-round use generally have at least 2000 mm; expedition tents intended for extreme conditions are often rated at 3000 mm.