3M Butyl Mastic Tape 2212 is a high tack, self fusing butyl rubber mastic ideal for making water and humidity resistant seals. Butyl Mastic Tape 2212 may be overwrapped with vinyl tape to create a reliable weatherproof seal around cable connections and other weather sensitive devices. It maintains its tack and flexibility to temperatures as low as 0F ( 18C), ensuring a high quality seal over a wide range of temperatures.