The cigar box opener is a manual tool with which one can open a cigar box.
It has a flat, rounded, blunt blade with a small notch along the side, and a straight handle. With the rounded end you cut the paper band around the lid of the box loose and with the notch you pry the nail loose. In some models there is also a hammer head present to hammer the nail back in. Sometimes the cigar box opener is combined with a cigar cutter.
The same tool is used to open boxes with scoops (1).
The cigar box opener can also be part of a pocket knife. [MOT]
(1) Paul Duflos. Outillage pour le travail du bois. Tariff No. 5. 1920: 13 marteaux-couteaux pour primeurs.