Stax SRD-4 Adapter for the Electret Earspeaker, is it of any use to me

[snowdog]

Found this sitting in my car I bought 2 days ago:

Googling gives vague results, it's some sort of adapter for some sort headphone with an odd plug I don't have ??? Is this device of any use to me, I don't have any electret earpeakers or whatever ? Why would one want this in a car anyways? Surely it isn't smart to wear headphones in a car playing music so you can't hear anything else from traffic like an ambulance or whatever ? Or is this some sort of handsfree kit? I really don't know.

 

[snowdog]

I thought some results did say it's some sort of handsfree kit but I have no idea how it's supposed to work I can't see any mics in the car or anything.

I bought a Volvo V40 ( nope, I couldn't afford a ''proper'' V70, it's my first car).

 

[snowdog]

Looks like it's a studio/home device for converting music form speaker outs to headphones...is it wired into the stereo?

Odd, I have no idea how or if is plugged/wired in, It just happened to sit there when I got the car .

Better than my first car.

Is it not a socked to the left of the dial?

Looks like it's been rammed in there though.

Yea it is I think, the socket is very odd it has 5 holes in a strange shape. See the pic:

 

[snowdog]

I see and found a website explaining it all to me, now the question is, should I get it out and flog it, or should I go hunt on ebay for some headphones ( and use it in the car or at home?) ? Or just leave it ?