The Greys Torsion Spyda Wynda System offers the ultimate in flexibility, stability and protection. The patented Spyda Wynda mechanism is at the heart of a new bivvy concept that aims to offer the dedicated carp angler something that can only be described as the ultimate bivvy. The bivvy also features an extended draft skirt that is particularly useful on uneven ground or when you need to go ultra lightweight and use the bivvy without the groundsheet. The Torsion Spyda Wynda system is simplicity itself to erect and the operation can be completed in under a minute. See how easy the Spyda Wynda is to setup at www.greysfishing.com . Once erect the bivvy is completely free standing and self supporting, all that is needed for extra rigidity is the addition of the door tension bar (included) Due to its design the bivvy can also be adjusted for height and width to suit changing weather conditions.