Strange tool in with my lug wrench

[Wild Turkey]

I found a strange tool in my trunk. In with the lug wrench was a 4" long steel tool with 21 mm male hex on one end and 12 mm hex on the other. I can't figure what it's for or find it in the manual:
1. Tool to convert a 21 mm socket to 12 mm Allen head? Odd since lug wrench is 19 mm, not 21 mm, so it won't work with that.
2. Tool to convert a 12 mm socket or wrench to 21 mm Allen head? What needs a 21 mm Allen key?
3. It's 1/2 lb. Added to balance the car when wiper fluid reservoir is over 1/2 full?

I found it when I went to check my compressor. Since I go through a compressor every 5 years in my Jeep, what was the chance my 26 year-old was still working? Still working!

 

[NSXGB]

Spark plug box wrench?

 

[Wild Turkey]

Spark plug box wrench?

It has a male hex on both ends, so I don't see how to use it for spark plugs.

 

[docjohn]

maybe it opens the Ark of the covenant..

 

[NSXGB]

Ah. I thought you were describing the box wrench. No clue what that is!

 

[Kaz-kzukNA1]

Not OEM but used for aftermarket tuner style lug nut.
Probably at some point before your ownership, someone had aftermarket wheel.

Kaz

 

[Wild Turkey]

Not OEM but used for aftermarket tuner style lug nut.
Probably at some point before your ownership, someone had aftermarket wheel.

Kaz

Ah yes, those "interesting" Volk GT-C's from Owner #2 . I should have thought of that. Looking at the pics I can see that style of lug nuts now. Binned - I've now lightened my NSX by 1/2 lb!

Thanks Kaz! You are encyclopedic!