Page 232 - Bob Holtzman "The Field Guide to Knots How to Identify.."

18. Slipped Square Knot

Also known as: Reef Knot or Hercules Knot with a Drawloop

A single drawloop makes this simple variation of the Square Knot (opposite)
easy to untie, even under tension. You probably know another variation,
called a Double Slipped Square Knot, in which drawloops are added to both
ends: it’s how you tie your shoes.

Uses: packages and bundles that must be tied securely and untied easily; bootlaces (when tied with two
drawloops)
Pros: easy to tie and remember; secure under load, unties easily

Cons: not very secure if not under load

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

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