When pulling,it must be smooth and there will be no feeling of pulling.When pulling,the sound is not very loud.it is not easy to pull the chain teeth with the hand. In addition to the pull head,there are also large and small bottom points. between the pull head and the pull piece, it is not easy to open.pull the film to be firm,not easy to pull,deformation and other phenomena,there is a color of the clothing chain should also pay attention to whether there is areinforcement color level.