Page 632 - Bob Holtzman "The Field Guide to Knots How to Identify, Tie, and Untie Over 80 Essential Knots for Outdoor Pursuits"

5. Both ends pulled tight. The leg of the crossing turn bears the load; the leg of the bight is the braking or
control leg. Pulling the braking leg tightens the crossing turn around the loaded leg and prevents it from
feeding out slack.

Uses: climbing: belaying, braking, rappelling

Pros: flexible, multi-purpose slide-and-lock hitch
Cons: kinks; can ruin rope if it runs too fast

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