Page 423 - Bob Holtzman "The Field Guide to Knots How to Identify, Tie, and Untie Over 80 Essential Knots for Outdoor Pursuits"

52. Zeppelin Bend

Also known as: Rosendahl’s Knot

This is a very strong, secure knot that will snug up and fair itself nicely
when first placed under load. It works well in equal-size cordage of any
diameter and can be easily untied, but the working ends sticking out in
opposite directions at right angles to the standing parts make it
inappropriate for dragging over ground or towing through water.

Uses: load lifting, safety
Pros: strong; remains secure when unloaded; easily untied

Cons: tricky to tie; bulky; may catch when dragged

Instructions (NB R1 = Rope 1, R2 = Rope 2)

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