Acquired Dovetailed Wooden Card Index for 4 x 6" Index Cards

Exterior dimensions: 6 11/16 x 4 13/16 x 3 15/16"
Unknown manufacturer

Picked up at thrift for $2.39. What can I say? I’m a sucker for card index boxes…

I can’t make out the smudged black-stamped bottom of the box to determine the manufacturer who used a sphere and a triangle in their logo.