A:
I received your inquiry through the Question and Answer Feature of Staples.com and I apologize that this requesting information was not available to retrieve. Because your inquiry is specific in nature it would be best resolved through the manufacture. They will be glad to help with your question. You may contact Staedtler-mars limited at (800) 776-5544 or (800) 387-5872.
Answered on 3/25/2011 by Laura B from Staples