The phrase "duty zippers" refers to zippers that are strong and reliable, often used in durable or heavy-duty items like backpacks, luggage, or work clothing. Full definition
These boots are water resistant and use a heavy duty zipper to keep water away from your feet. (geekwrapped.com)
This Lighthouse grow tent is tough: heavy duty zippers overlayed with canvas, a powder - coated steel frame, and double - stitched 900D canvas exterior with a tear - proof Mylar interior, all made to be non-toxic with no off - gassing. (geekwrapped.com)
So we made sure to mark whether each grow tent has heavy - duty zippers designed to stand the test of time or not. (geekwrapped.com)