tripwire for camping

This spring I was on a short camping trip to Svalbard, 78 deg. north. Due to the danger of polar bears it is mandatory to take necessary precautions to avoid injury from attacks (that is injury to both bears and people). One of several necessary precaution is to set up tripwires around the camp. I made these that can be attached to the skis with duct tape. Setting up tripwires requires knowledge on the subject as they are useless if set up wrong, and very dangerous, no kidding.

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