It's got all the banned features! Collapsing stock, pistol grip, detachable magazine, bayonet lug, threaded muzzle, flash-hider and grenade launcher.
Yes, Troubleshooter, grenade launcher.
That's a NATO compliant M16A2 flash-suppressor screwed onto that threaded muzzle.
It's nearly as useful as the bayonet lug (which can't be used because the muzzle is 1.5" too far from it).
If I were to find someone willing to sell me a NATO spec rifle grenade, I could fit it to my muzzle device and fire it. After I filled out an ATF form 5320.4, paid a $200 transfer fee, and passed an extensive background check I could, in theory own the Destructive Device known as a rifle grenade. The companies that manufacture them do not sell them to individuals. Last time I checked, that included sales of even the inert practice rounds.
The only rifle "grenades" I have ever seen for sale are the inert practice rounds for the spigot launcher attachments for the M1903 and M1 Garand.
I don't know why "grenade launcher" was included in the assault weapon ban, but it sure wasn't ready availability.