... 4:1 color: black, transparent good performance teflon, ptfe heat shrink tubeGRADE:SB-PTFE-HSTOperating Temperature: -80°C~260 ... applied imported polytetrafluoroethylene (PTFE). PTFE heat shrinkable tube has excellent chemical resistance, heat resistance, weather and corrosion resistance. ... , etcEnvironmentNo hazardous to humans and environment SGS high temp resistant ptfe heat shrink tube (1.7:1/4:1)