Amongst the sample pen kits that I recently purchased was this one. The importer has no details regarding assembly, and I am too in-experienced regarding pens to figure out how it goes together, also diameter of bushes needed. The tubes are 10mm and the two round pieces on the right which look like plastic are, I'm sure, metal. At $5.13, it seems very good value, providing someone can head me in the right direction.
Nothing but heaven itself is better than a friend who is really a friend. - Plautus