Four way stretch this fabric offers cross and lengthways stretch thus providing excellent freedom of movement semi autolock zipper the zipper slide in this garment features a special locking system that prevents annoying jingle windstopper174the windstopper membrane is an ultra light coating which is laminated on a light fabric and provides absolute windproofness it is made out of the polymer ptfe polytetrafluorethylene which is stretched to achieve a pore structure the micro pores a