HELP: Unknown Muzzle Break with threads at both ends

[abartpear]

Found this at an estate sale over the weekend. The seller did not know what it was. It looks to never have been used. It has both male and female threads and about 9mm is with. If you Dave any ideas what this could be for please share.
'Thank you,

Read More

 

[arrowshooter]

Could be:

L.A.W. Muzzle Brake and Cap 5/8-32 - Pacific Tool and Gauge

L.A.W. Muzzle Brake and Cap. Highest Quality Firearm Parts Made in White City Oregon USA.

pacifictoolandgauge.com