Key takeaways
- A sling (runner) is a sewn loop of webbing or cord — among the most versatile climbing tools.
- Uses: building/extending anchors, extending protection to reduce rope drag, slinging features, tethers, rescue.
- Materials: nylon (stretchier, durable, cheaper) or Dyneema (lighter, thinner, low-stretch).
- Common lengths include the single (60cm) and double (120cm) shoulder-length sling.
What a sling is
A sling — also called a runner — is a loop of strong webbing or cord, usually sewn closed, and it’s one of the most versatile items on a climbing rack. Cheap, light, and simple, a single sling can serve a dozen different purposes on a climb.
Common uses
- Extending protection (with carabiners) to reduce rope drag.
- Building and equalizing anchors.
- Slinging natural features — a tree, horn, or chockstone — often with a girth hitch.
- Personal tethers to clip into an anchor.
- Rescue and improvised systems.
On a wandering trad pitch, a climber extends a piece of protection with a shoulder-length sling so the rope runs in a straighter line — cutting rope drag that would otherwise make the upper moves feel like dragging an anchor.
Materials and lengths
Nylon slings are durable, abrasion-resistant, slightly stretchy, and cheap; Dyneema slings are far lighter and thinner but have almost no stretch and a lower melting point. Common lengths are the single (60cm) and double (120cm) shoulder-length sling. The pre-made, fixed-length sling-plus-carabiners unit is a quickdraw.
The bottom line
The sling is climbing's Swiss Army loop — a simple sewn band of webbing or cord that does a dozen jobs, from extending protection and building anchors to slinging trees and rigging rescues. Carry a mix of lengths, choose nylon for durability or Dyneema for weight, and you'll reach for slings constantly on any climb.
Frequently asked questions
What is a sling in climbing?
A sling (also called a runner) is a loop of strong webbing or cord, usually sewn into a closed loop, used throughout climbing. It's one of the most versatile items on a rack — used for building anchors, extending protection, slinging natural features, making tethers, and rescue, among many other tasks.
What are slings used for?
Common uses include: extending a piece of protection (with carabiners) to reduce rope drag, building and equalizing anchors, slinging a tree, horn, or chockstone as an anchor point, creating a personal anchor or tether to clip into an anchor, and improvising hauling or rescue systems. Their simplicity makes them endlessly adaptable.
Nylon or Dyneema slings?
Nylon slings are more durable, more abrasion-resistant, stretch a little (absorbing some shock), and are cheaper; Dyneema (Dpolyethylene) slings are much lighter, thinner, and stronger for their weight but have almost no stretch and a lower melting point. Many climbers carry a mix, choosing nylon for anchors and Dyneema where weight matters.
Sources
- Slings & anchor building — American Alpine Club
- Climbing gear standards — UIAA