The gun appears to be a D-Grade, DE-Grade if it has ejectors. "Normally" the grade is stamped on the left watertable --
121252 DEO-Grade 09 watertable.jpg
or on the "bridge" if the gun has what Charles Semmer referred to as the "bridge frame" --
101315 BE-Grade 12-ga 07.jpg
I have seen a handful of Remington Hammerless Doubles that I would consider to be D-/DE-/DEO-Grades that were not stamped.
A DEO-Grade would have "Ordnance Steel" barrels --
P132688 06.jpg
Normally 12-gauge Remington Hammerless Doubles were made for 2 5/8 inch shells. If ordered for longer shells, it was stamped on the bottom of the barrels just forward of the barrel flats --
121252 DEO-Grade 07 2 7-8 inch chamber marking.jpg
According to Charles' serial number chronology 110960 would be from early 1899.