Type: Mechanical pencil lead Pilot, Darkness: 2B (Some do not explicitly state 2B, but it is likely the same) 12 leads per case x 5 cases Thickness is not specified, but measured with calipers, it appears to be 1mm. This is an amateur measurement, so it may not be accurate. I apologize if it is incorrect. (Since it's not specified, was 1mm the standard for mechanical pencil leads during this era...?) These have been stored for sale for about 50 years. While I cannot guarantee the quality, they are not broken, and they don't seem to be brittle and easily breakable, at least for now. Some of the case labels are peeling or partially torn. I would be happy if someone appreciates the retro feel and finds value in them. Thank you for viewing.