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The belayer provided a 50m rope for a 28m climb, believing it to be 60m, and didn't use a stopper safety knot. As the climber, I trusted the belayer and didn't check the length or check for a stopper knot. Subsequently, I fell off the end of the rope on the descent and fell approx. 4-5 meters. I required mountain rescue and hospital treatment, but the injuries were soft tissue and whiplash, so very lucky escape.