... : EN 60947-1:l2007 (CLAUSE 7.3,8.4), class of fire proofing, little smoke and halogen, no firing encounter fire, ... , then cover Characteristic:1,combined strongly, no taking off, smoothness of the surface, no hurting hands and mangling the thread nearby ... .2,hard to break, color changing, distortion under the temperature of 70 degree.3,low thread hole, easy combination, take down ...