That isn't arm hair!!!!!
Don't buy knives from Amazon. This is the kind if BS that ends up happening. I'm going to say this yet again, for the 1,000th time - Buy from legitimate and reputable dealers that sell and deal in knives only/primarily. They know their products, they can tell what is real and what is counterfeit and you get a DNA free knife every time. The cost of saving a few bucks is often more than just paying what the item costs outright. People just don't learn.
I would be willing to bet money that Amazon does NOT check for returned knives, they have their staff on a specific schedule to acquire, package and ship the item, Fast! Fast! Fast! Those people deal with tens of thousands of items from toe nail clippers to water bottles, they don't know knives any better than they know other products. There was a story about a used Benchmade 710 that made the rounds to 2 or 3 different people on this very forum, it was the exact same knife. Each time it was returned they just threw it back on the shelf. It was a used 710, and no one bothered to follow up on the complaint the first or second time around. Come on people.