I think it's just a typo - I found it on the 4/27/10 post, number 28 on page 3 but can't figure out how to link it... Here's what Alaskasunshine says in that post.
"If you call a local sign shop just ask if they carry the sign material that is corrugated plastic for signs. Usually realtors have for sale signs made of this stuff. They come in 4'x8' sheets. My DH cut them up for me. If you are not able to do that they may cut them for a fee.The only thing to be careful of is making sure your lines are going the right way otherwise the bolt will fold up as you try to wrap it. I give that information on the first picture on this tutorial.
have lots of fun with this. Also if you have more questions feel free to ask away...
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