The Volunteer Commando Mark 45 an updated version of the
Mark III . Sometimes also called the Mark V. They are very similar to the Mark III except
that it uses the military Thompson Butt stock , actual Thompson stick
magazines , and the lower frame is plastic with a plastic "wood look"
pistol grip instead of the pot metal frame that the Mark III uses . The
Mark 45 is also chambered in .45 ACP . I've heard that sometimes the
Thompson magazines will need to have the catch elongated to properly
latch into the Mark 45 but don't own one personally so take that for what it's worth.