The utility model relates to a rotary two-pole flat plug, suitable for a two-hole and three-hole flat jack socket using an AC power supply.

一种可旋转的二极扁插头，适用于交流电源两、三眼扁插孔插座。

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Toward the right, you've got the USB type B connector that runs to your laptop, the AC adapter jack, and the master power switch.

ENGADGET: Native Instruments Traktor Kontrol S4 review Alt

Yes, that's right, we said AC adapter jack: unlike the X1, the S4 can't be driven off bus power alone, unfortunately.

ENGADGET: Native Instruments Traktor Kontrol S4 review Alt