Duct and Insulation Tapes 600 Series   –  Printed, metalized, waterproof, polycoated cloth   –  Printed, metalized, waterproof, polycoated cloth; natural rubber adhesive. Designed specifically for HVAC industry for use on Class I flexible duct installations. No adverse effects after exposure for 60 days at 212 degrees F. Meets Spec: UL 723, Flame Spread lndex-15, Smoke Development lndex-30.   –  Carolina Tape   –