anyone recognize this forearm wrench

[Gunsnrovers]

Was looking to pick up a forearm wrench for my 870 and saw this one advertised.

http://i13.ebayimg.com/03/i/03/18/85/6e_1_b.JPG

I know it won't work on my 870, but was wondering if anyone knew what shotgun it was for.

[Onmilo]

That wrench is used to unscrew the end metal from a semi-automatic shotgun forend.
Which one, if it isn't marked, would be trial and error.

[MOAMike]

It could be for a Mossy pump forend. They are a slightly different size than the ones made for the 870.

Good Luck
Mike