Opt for our 3M 8420 Cold Shrink Connector Insulator when you need primary electrical insulation for applications rated 1 kV. It s made from super strong EPDM rubber for good performance, and it provides an environmental seal that protects against alkalis, acids and ozone. This open ended tubular sleeve operates in temperatures ranging between 40 to 194 degrees F 40 to 90 degrees C .