1、If you have a zipper head that can cause a toothless obturator failure when it is unflatted.This ia a paraffin and lubricant coating that can be used on the surface of the zipper tooth and inside,and then slides the pull head several times.2、zipper sometimes bite the head of line or chain head motionless,in this case,if the mobile is strong pull head,will be more and more deep bite,so please slowly backward lab untied,when sewing zippers,please don’t leave hidden trouble.3、Install too many zipper bags,If  the zipper is closed,the zipper will be too large and the tooth will be damaged,It is recommended that you close the surrounding teeth and easily make the chain head by closing the zipper.4、will head to the bottom seam allowance,around to pull teeth were divided into two parts,the pull of left and right sides of the zipper teeth can,to measure the needed to stop destruction force,as well as the measuring head resistance internals,avoid in the process of purchase zipper used after fault occurs.First of all,fasteners unit in a tablet,it is a state of nature,then pulled out a steel ruler,measuring from the top of the head,measure leading to the outside of the fastener end ,if the open end of the fastener,the outer end of the number to the export.