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More than likely, you shotgun is the Model 1900 (from the markings) and will have a removable hinge pin. With that serial number, we can guesstimate it was made around 1908 - 1910 - no s/n to year records are available - so guessing based upon estimated production rate since intro in 1900-01.
Check out the two pics below. First one should confirm it is a Model 1900 - with a view of the markings you can't read. Second is a view of the Model 1908 with a fixed hinge pin and snap off fore stock. Your piece may be a 1908, if pin is fixed in place - but with those markings I doubt it.