Q: Which zipper fits climbing pants?
Climbing pants take a size 4.5 nylon coil fly with a closed-end bottom stop, plus a size 5 coil for any leg zip on a convertible style. Coil is chosen for the fly because it bends with the crotch seam and does not abrade a harness or a rope the way metal teeth do. The slider should be low-profile with a locking pull, and the bottom stop must sit above the crotch seam so it never presses into the wearer when a leg is lifted high.
- Size 4.5 coil fly, closed-end; size 5 for leg zips.
- Locking pull and a small slider body.
- Reinforced bar-tacks at both ends of the fly.
The common pitfall is specifying a metal zip for perceived durability. On granite and on a harness, metal teeth scuff the rope sheath and the anodised finish wears into a sharp edge. The second error is an over-long fly: it looks fine standing but digs into the hip in a high step, and the extra length also puts the bottom stop below the crotch seam where it chafes.