It is an insulating tape (self-bonding). Self Amalgamating Tape (High Voltage Tape) is used in joints and terminations for insulation and sealing applications up to 66kV. Self Amalgamating Tape when stretched and applied over its own layers, it amalgamates. It applies a positive pressure over the substrata. https://thepcatech.com/product/self-amalgamating-epr-insulating-tapes/

Self Amalgamating Tape | High Voltage Tape | HT EPR Tape

It is an insulating tape (self-bonding). Self Amalgamating Tape (High Voltage Tape), (HT EPR Tape) is used in joints and terminations for insulation and sealing applications up to 66kV.