The ballonet inside the survival pack can be aerated and placed into the bag to postpone the sink time of the survival pack, so as to help a drowned person catch the survival pack.

救 生包内小气球使用时，吹大来放入袋子中，可延缓救生包下沉的时间，以利 于溺水者抓住；

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As Hansen piloted our little boat past a series of snow-crested peaks, he showed me the survival pack he had thrown on board.

BBC: Kluane, Canada (Credit: Parks Canada/Fritz Mueller)