EdGI Custom Works make some of the finest products in the world and these barrels are no exception. 

Custom made to our specs, these barrels are internally lapped to a mirror finish for extreme consistency. 
They feature a 6mm square cut window to make R-Hop and flat-hop installations a breeze and can be easily installed in virtually every AEG hop chamber. 

We've chosen 6.02mm as the inner bore diameter to balance efficiency and reliability. 
280mm in length is perfect for all 10" outer barrels; you'll typically see around 5mm protrusion from the outer barrel which makes installing stabilising shims much easier than a recessed barrel. 
This is still fully covered by virtually all flash hiders.