Page 275 - Bob Holtzman "The Field Guide to Knots How to Identify.."

Uses: lifting large heavy loads, bosun’s chair,

or rescue harness
Pros: loops will not shift under load

Cons: difficult to tie with loops of unequal

size

43. Alpine Butterfly

Uses: mid-rope tie-off point, purchase for
tightening a line

Pros: easy and quick to tie; suitable for loads
in either direction

Cons: only useful on a bight; awkward to tie
large loops

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