Shurtape PC-622 Contractor Grade Duct Tape is a 12.5 mil thick premium-grade duct tape used for HVAC duct systems; the protection of window and door frames during stucco application; high performance motorsports applications; silk screening; and heavy duty bundling, sealing, seaming and splicing. Shurtape PC 622 has high tensile strength, is conformable, and has excellent holding power. UL 723 listed.