Mastic Tape is a highly stretchable elastic element which provides a mega-stretch up to 100 times of its original length. It is a rubber based insulating compound which is derived from self-fusing butyl. It is provided with a poly vinyl chloride backing which acts as the primary insulation. This flexible can be easily applied to make an insulating barrier or a moisture seal to an object with intricate shape. Mastic Tape is also very efficient for the heat ventilation and air conditioning systems in case to prevent leakage from the system.