Page 194 - Bob Holtzman "The Field Guide to Knots How to Identify, Tie, and Untie Over 80 Essential Knots for Outdoor Pursuits"

13. Sink Stopper Knot

This stopper knot is larger than Overhand or Figure 8 Knots and will stop a

rope through a significantly larger hole, but it’s shorter and less obtrusive
than the Stopper Knot.

Uses: stopper, especially in thinner rope

Pros: stops holes larger than many other stopper knots

Cons: very difficult to untie if tightened hard

Instructions

1. Make a counterclockwise overhand crossing turn. Form a bight in the standing part.

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