Mechanical four-digit counter with two levers and mounting plate on top. Big lever resets count to zero. Smaller one increments count, and was probably meant to be tugged on by a stiff wire or a string. Either lever rotates downward by about 50 to 60 degrees.
Modeled from memory. A grandparent gave me this counter when I was a kid. Made in early 1960s. Now lost, so manufacturer, exact size unknown. Width of main box should be about 3 inches, or 7 to 8 cm.
Blender file only at this point.
Simple, clean materials. You'll probably want to add scratches, scuffs, fingerprints. Digit wheels are UV-mapped, with digits image applied to a main band around the circumference. Rest of digit wheel is UV-mapped to a small background sample of the digits image for matching color; for fancier texture you'll want to relocate these UV pieces. Rest of device uses simple Blender Internal materials, no textures.
Parts are parented to main box. Intended for simple still scenes, or very simple animation - no rigging, no constraints keeping the levers tied to the axle. Feel free to rig and constrain as you like.
Main box, top plate, window are on one layer. Levers, axles and other parts on another. Digit wheels are on a third layer to make rotation easy. Camera, lights used for demo renders are on a separate layer.