Please reach out to Hogue directly for an answer to your question. That information is not stated on the website.
Yes it is 15 inches in length
We have two thread patterns for AR10 Armalite and DPMS if your upper is not patterned off of one of these it will not work, you will low profile gas block for this forend.
-DPMS #15060 with a 1 7/16"-16 TPI. Will have 22 holes on perimeter.
-Armalite #15061 with a 1 7/16"-18 TPI. Will have 20 holes on perimeter.
Yes as long as you have a low profile gas block.
These are free float so they will fit any gas system length as long as you have a low profile gas block. They will not fit a mid-length system if you do not have a low profile block.
No, these are not compatible with the DOLOS system.
It is a 15" handguard.