This is a calligraphy brush from Ippodo, made with weasel hair (itachi-ge). It retailed for 2000 yen and has been stored at home. Total length: 23.5cm Brush handle diameter: 4mm Bristle length: 27mm Brush tube diameter: 7mm Unused. Can be used for calligraphy, Japanese painting, and watercolor painting. I'm not sure about the writing feel, but it seems like it would be good for fine lines.