A slide fastener stringer includes a stringer tape having a pair of opposite surfaces, and a series of fastener elements attached to the stringer tape on one of the surfaces thereof along its one longitudinal edge by use of single needle double locked stitches composed of a needle thread and a looper...http://www.google.es/patents/US4319387?utm_source=gb-gplus-sharePatente US4319387 - Slide fastener stringer
