[Researcher]

In the hammer gun era Parker Bros. had the distinctly bulbous pistol grip that many collectors call the "ball grip" and many mistakenly apply that term to the half-pistol grips of the hammerless era.

Most Parker Bros. catalogs just state "straight or pistol grip" --

Quality G.H. Blue Ink Catalog.jpeg

Quality G.H. Ejector Catalog.jpeg

GH & GHE 1923.jpeg

January 1, 1930, Parker G.H.E - Parker G.H.jpeg

By the Remington era they specify the "half pistol grip --

Parker Skeet Gun, May 17, 1937, grip styles underlined.jpg