Attaching SKS muzzle brake

[Supplier365]

Anyone have an idea how this muzzle brake is attached to the end of this SKS. I can't see any screws or such and just wondered before I hit it with a torch. Your insight is highly appreciated.

 

[backinblack]

Usually screwed on, possibly left hand thread, possibly a small pin. I was going to pull the grenade launcher spigot off the end of my Yugo a long time ago. No heat nor chemicals got it to budge. I stopped messing with it before I damaged anything.