A folding bone (also called bone folder/bonefolder) is a dull-edged hand tool traditionally used by bookbinders

for example

Timeless designed ballpoint pen available in several different colors

18-pack of Tombows ABT Dual Brush markers including eighteen selected pastel colors

The pencils is delivered unsharpened and is available in 17 different degrees of hardnesses: 6B

ballograf ballpoint pen desk set dusty green hiddenproduct A folding bone (also calledA true Swedish classic. The Ballograf Ballpoint Desk Set was introduced in 1961 and was a compulsory feature in most Swedish bank and post offices from the 1960s onwards. A wonderful Swedish design classic who moved from bank and post office in Sweden to designer stores around the world. The pen comes filled with blue archive proof ink. The pen is refillable and has lifetime warranty. Made in Sweden.