I like to use B72 the most. The pen I tend to pair it with is “pigma micron 05” http://www.gaylord.com/adblock.asp?abid=16098&search_by=desc&search_for=micron%20pen&mpc=WW. Typically I write the number on rice paper and use B72 to stick the rice paper to the object. I find that the number shows nicely doing this, and is less like to smear. However, I have not had any smear problems with this pen. Hope that helps!