Wind it like a watch with a key that's stored underneath the barrel, and when it's 'fully loaded' use your thumb to pull back the safety lever. Then squeeze the trigger.

用放置在枪管底端的转柄给它像手表一样上发条，当发条“全部上满”之后，用你的大拇指向后拉动枪栓，然后扣动扳机。

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The switch is directly fixed on the trigger while the inside of the holding portion of the hand lever has a trigger rib which is relatively arranged to a contact point on the switch.

所述开关 直接固定在扳机上，同时所述手柄握持部位内设有同该开关上的触点相对的 触发筋。

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Insert a foil pack of powdered insulin into a slot, prime the pump with a lever and push a trigger that releases the cloud of insulin into a clear plastic chamber.

FORBES: Magazine Article