Hello:
I was trained to draft in high school. I really liked it. Was given a Alvin Draft/Matic mechanical pencil by one of my teachers. I still have it. They come in several different hardness values. I use a a 0.7 mm for normal work and a 0.5mm for drafting mountains. I have used these pencils for years a love them. You can find them in art supply stores. I have around 9 of them now and the last one I purchased was four months ago for a gift. They run around $9.00 to $15.00 U.S. I do like them.

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