Can you spot the difference between these two Lugers?
One of these things is not like the other:
On the left, you have a DWM-made M1900 Luger in 7.65 with a skinny barrel, dished toggle knob, and push-grip safety, among other features. On the right is a gun that was made just 15 years later, am Erfurt-produced P08 in 9x19mm Parabellum with a thicker barrel, serrated toggle, and no grip safety.
Fundamentally, the one of the left is a commercial model, based on the original Luger adopted by the Swiss Army in 1899, and made for export, while the pistole on the right was the German Army standard for the Great War.
Further, the M1900 is an American Eagle, a breed of guns that proved unusually popular on the U.S. consumer market with Western lawmen and cowboys in the 1900s and 1920s.
More on the American Eagle Luger in my column at Guns.com.