Don't leave home without it! The Gecko is a simple, lightweight fleece pullover and has been a mainstay of Jack Wolfskin's collection for many years. It is made of 100-weight microfleece and is incredibly versatile. Wear it as a mid-layer in your layering system. Slip it on during rest breaks to stop you getting cold. Or prolong your evening outdoors with a bit of light insulation. It's a practical, basic piece suitable for a wide range of activities.