Coil Zips
A coil zip (also called a nylon coil zipper) uses a continuous coiled nylon filament stitched onto the zipper tape. It's flexible, lightweight and smooth to operate. Coil zips are commonly used in tents, backpacks, jackets and sleeping bags.
What does the # number mean?
The number (e.g. #5, #8, #10) refers to the width of the zipper teeth when closed, measured in millimetres:
#3 = 3 mm wide (small, often used in pockets)
#5 = 5 mm wide (standard for most tent doors)
#8 = 8 mm wide (stronger, used in higher-stress areas)
#10 = 10 mm wide (very heavy-duty, common on large tent entry points and awnings)
Higher numbers mean larger, stronger zips, but they can be heavier and stiffer.
Why use coil zips on tents?
Smooth operation, even around corners or curves
Resistant to jamming and dirt
Lightweight but strong
Can be repaired or replaced relatively easily