The Thorobred pencil, made in the 1935-1939 period, corresponded to the #3 lever-filled fountain pen. It uses the older 1.1 mm lead, the cap twists off to reveal an eraser, and the mechanism works by twisting the black and silver tip. The ball clip has Waterman's imprinted on it, and there is an imprint on the back of the cap which says, "Waterman's, Reg.US Pat. Off., Made in U.S.A."
With the Thorobred, like a solemn butler or aide de camp, comes this Waterman pencil, the Commando model of the 1940s. It has gold-tone "military clip" and trim, and although it looks like a repeater, it is a nose-drive mechanism advancing 1.1 mm lead.
A thoroughly Waterman pair.
For more Waterman Thorobred pencils, see this blog: