3 Contact (TRS, Tip Ring Sleeve) 3.5mm socket, typically used for stereo headphone.
Standard solder tabs.
Nut fastening behind the panel for a clean bezel look in front.
For headphone wiring, fairly universally, the Tip is Left, Ring is Right and Sleeve is Ground
Can't say much more about this, not really very exciting, but if you need one, you need one.
Of course, not limited to audio usage, 3.5mm plugs are convenient means for connecting up sensors and such to your electronic projects. I've even seen cheap handheld oscilloscopes using 3.5mm jacks for their probes.
Be sure to see my other audio plugs and sockets listings
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