Ahh... when I found out that I needed something smaller than 0.5 mm lead I tried 0.2 and 0.3 lead but 0.4 was it. I bought all currently available 0.4 mm mechanical pencils, that makes 14 pencils from Mitsubishi, OHTO, Pentel and Pilot. Plus the nicest of them all, Pilot S20 0.5 modded to 0.4.