I saw someone using something that looked like a PDA with a small attachtment to scan books for value. What is

Question

I went to a used book store and saw a customer scanning books with something that looked like a PDA with something that looked like a cartrige attached at the top and he was using it to scan books for their value. He was a reseller. Does any one know what it was and where I can get one?

Answer 1

scanner