When returning empty cylinders, close the valve before shipment. Leave some positive pressure in the cylinder.

返还空瓶时，在运输之前关闭阀门，使钢瓶内部保持 正压 。

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Revolvers shall be presented with the cylinder swung out and empty. Self-loading pistols shall be presented with the magazine removed, the chamber empty, and the slide held or locked back.

转轮手枪须将转轮转出并清空，而自动手枪必须卸下弹匣、清空药室，并将滑套固定在后。

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