Steadtler Lead Holder Series.
Mars 1002 (2nd generation) J.S. Staedtler, Nürnberg, Bavaria lead diameter mechanism composition variations production date origin 2 mm (slightly thicker for softer leads) twist lock clutch wooden barrel, metal clutch, ivory endcap 17 degree imprints: ... 3B, 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H, 7H ... (precise range unknown) 1924 to 1934 Bavaria Mars Lumograph 1018 J.S. Staedtler, Nürnberg, Ger..