Page 27 - Bob Holtzman "The Field Guide to Knots How to Identify.."

Never use bungee cords to secure loads to a car’s roof rack

It bears repeating: test every knot before relying on it for safety.
Improperly tied knots – and properly tied knots that aren’t right for the job –

can slip or untie themselves unexpectedly, with potentially life-threatening

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