Duct tape and Duck Tape® are often used interchangeably, but they aren’t quite the same thing.
Duck Tape® vs. Duct Tape - Ducktape
The [Complete] Technical Guide to Duct Tape
The [Complete] Technical Guide to Duct Tape
PC 619 Duck Pro® by Shurtape® General Purpose Grade, Specialty Grade, Fluorescent Cloth Duct Tape - Shurtape
Duct Tape Types General, Industrial, Gaffer's, Stucco Tape
Is It Duck Tape or Duct Tape?
Gaffer Tape vs. Duct Tape: What's the Difference? - Tape Jungle
Is it 'duct' or 'duck' tape?
Duck Brand 1.88 x 100', Clear All Weather Repair Tape
3M 2.83 in. x 30 yds. Multi-Use Duct Tape 2930-W - The Home Depot
3M 8979N Nuclear Grade Duct Tape - 2 x 60 yds, Slate Blue S-17542BLU - Uline