Identify this gas block please!

bcw1284

Gunny Sergeant
Full Member
Minuteman
Mar 18, 2008
1,821
2
39
Cheyenne, Wyoming
I am having trouble figuring out what the hell this gas block is. It fits AR-15 with the .75" barrel. It has a hex shape, 4 screws to clamp on, and a circular hole in the bottom part.

HELP! thanks.

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