Several distinctive characteristics distinguish the 1941 Replica from today’s familiar Zippo windproof lighter. The 1941 case has flat planes with sharper, less rounded edges where the front and back surfaces meet the sides. The lid and the bottom are joined with a four-barrel hinge, just as they were on the original 1941 design. The current Zippo lighter has a five-barrel hinge. The inside unit closely replicates the design of the original 1941 model inside unit. Like the outside, the sides of the inside unit are flatter, with squared edges where they meet the front and back surfaces. The inside unit has fewer holes in the chimney, and is also fitted with a hollow rivet that holds the striking wheel in place.