3M 1599B Silver HVAC Tape
Model NED-26311
Seal flexible air ducts and HVAC connections. Long lasting, all-weather construction tape. Resists moisture, flames, UV and chemicals. Meets UL 181B-FX for flexible duct sealing. Handles temperatures from -40º to 85ºC (-40° to 185°F). Shiny silver polypropylene backing with acrylic adhesive.