I seem to be getting the hang of posting photos and I did get a new iPad Pro that has an excellent camera. So I thought I would do this thread with the newest i.e. the iPad, showing the oldest Hardtmuth’s I have. The No.48 is a 5.6mm and the rest are in 2mm. You adjust the the lead by turning the front knurled section and it will loosen its grip on the graphite and then you adjust the position to the length you want. These were made at the Bloomsbury, New Jersey plant. Metal and wood, my two favorite materials.
The 48 is interesting as I found it not here state side, but in Russia! I would love to hear its story if it could talk. I believe these are from the 1920-1930s. Not 100% sure.