These are some simple segmented pens that I have made. I kept photos of these for one reason or another. They are just cell phone photos and some not good at that.
The first one I made for my brother. It is Harley colors and he was a Harley guy. The second is a pen and pencil set I made for my wife. The third, another black and orange was made for an Athletic Director at a school we photographed for. The last pen was made for a friend upon his retirement from our PD. It is a thin blue line pen on a bolt action pen...its not really segmented, the blank came like that.
Typically, the white thin sections in the segments are "pick guard". That is the material on a guitar where the pick would impact the body of the guitar, and this keeps it from scratching. I order it from Stewart-MacDonald, a guitar makers supplier. (Luthier) I also use, old credit cards, hotel door Keys and knife grip material, if I want thinner lines. But I have used tons of stuff, from flashing to sheet material at hardware stores to any kind of pieces of plastic.