Collector technical vocabulary
Hinge barrels
The hinge joins the lid and case. Glen’s Canadian comparison shows equal five-barrel spacing generally through 1955 and unequal spacing generally from 1956 onward; component overlap and old-stock use mean this is supporting evidence, not an exact date by itself.
Source and interpretation
Sources: Glen's Zippo Page — Historical bottom-stamp, case/insert construction details, Canadian dating chronology, and transition research
This feature is supporting evidence alongside the case stamp, insert and other manufacturing clues. An individual component can be repaired or replaced.