He got sheets of 4 perforated and then bound with a gum binding (like a pad of paper). He then whips out the book and pulls a $2 off of the perforation.
He'll carry larger sheets folded up and then cut a bill out with scissors in front of the person he is paying it to. Apparently he got the secret service called on him once.
http://archive.woz.org/letters/general/78.html
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If you want to buy uncut bills you can yourself, but there's about a 50% markup on even the largest sheets:
https://www.moneyfactorystore.gov/2currencysheetsbeptestshee...