This performance specification covers zippers to be used as fly closures in dungarees, jeans, and work trousers made from heavy denim or other durable fabric. Zippers covered here may be satisfactorily used for lighter weight denim and other fabrics as well, however, consideration should be given to the zipper size and slider type because of their effect on the appearance of the zipper installation area. Zippers shall be suitably sampled and tested, and shall adhere accordingly to the following requirements: element pull-off resistance; element slippage resistance; crosswise chain strength; bottom stop holding-stringer separation strength; top stop holding strength; slider lock holding strength (positive and ratchet lock); slider deflection and recovery after pull (deflection and permanent set); resistance to pull-off of slider pull; slider operability on chain; longitudinal dimensional change after laundering (normal and low shrinkage level); and colorfastness to laundering (color change and staining). It is recognized that for purposes of fashion or aesthetics the ultimate consumer may find acceptable trousers having zippers that do not conform to all of these requirements. Therefore, one or more of the requirements may be modified by agreement between the purchaser and the supplier.

1.1 This performance specification covers zippers to be used as fly closures in dungarees made from heavy denim, approximately 475 g/m (14 oz/yd ).

1.2 Zippers covered by this specification may be satisfactory for lighter weight denim and other fabrics.

1.2.1 When lighter weight material is being used, consideration should be given to the zipper size and slider type because of their effect on the appearance of the zipper installation area.

1.3 The values stated in other acceptable metric units or in other units shall be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system must be used independently of the other, without combining values in any way.