The utility model is mainly formed by the connection of a movable lock catch (2) and a fixed lock catch (6) via a pin roll (5). The movable lock catch is provided with a lock tongue plug jack.

它主要由活锁扣片（2）和死锁扣片（6）通过销轴（5）连接构成，在活锁扣片上有一锁舌插孔。

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However, the headphones can also be connected using a normal 6.3 mm jack plug.

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Soon enough, Dorsey had engineered a tiny swipe reader that could plug into the headphone jack of an iPhone or iPad.

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You plug a phone into the jack, and calls are carried over your broadband Internet connection.

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