PVC Heat Shrink Tubing is a thin-wall, low cost material offering good electrical and mechanical characteristics. When exposed to heat in excess of 80 degree for a few seconds, the specially formulated polyvinyl chloride material will shrink rapidly and uniformly conforming to the shape of the object to be covered.Heating Tools: hot air or hair dryer (not included here).Applications used for protecting or repairing the cover of 18650 battery.Notice: the battery is not included here.