This is Scotch, not Duck Tape, but this brand remains my favorite. Better value than "original" 3M tape and basically just as good (although it's a bit harder to get a clean break and almost no noticeable difference in adhesion). For all your ducting or general purpose needs, this is a great choice (professional HVAC contractors can choose 3M). Note: Like all tapes, this one leaves a lot of residue, especially on plastic. Gaffers Tape is what you need for a residue-free stick, but it will cost you money!
Transparent Cross Strapping Tape: XFasten Filament Duct Tape 2X30 Yards - 3 Pack
29 Review
TapePlus Gaffer Tape - Large 2 Inch X 40 Yards Roll - Versatile Black Tape For Gaffers, Ducts, Floors, And More
31 Review
XFasten Super Strong Duct Tape, White, 2" X 50 Yards Waterproof Duct Tape For Outdoor, Indoor, School And Industrial Use
33 Review
High Tensile Strength Duct Tape Silver, 5.8mils, 2 Inches x 50 Yards - All-Weather Duct Repair Tape for Commercial Use, Heavy-Duty Repair, Packing with Temperature and Shear Stress Resistance - XFasten
39 Review