You order a product at Amazon.com and get the product from the vendor specified in the product listing, right? Not necessarily. According to this article in the Wall Street Journal, Amazon sometimes fulfills orders for products with "like" items that carry the same bar code.
It's might not be a big deal -- unless the replacement product happens to be a counterfeit, which apparently does happen, according to the article. That could be a real problem if one of your customers buys a counterfeit current-carrying electrical product on Amazon.com. This material from the article is enough to give any electrical products marketer the chills:
"As more third-party sellers have signed up to offer products through Amazon and use its order-fulfillment services, the Seattle-based giant has allowed many to pool their inventory with supposedly identical items supplied by other sellers—in essence commingling products from third-party merchants with those supplied directly to Amazon by the brands themselves...In other words, a product ordered from a third-party seller may not have originated from that particular seller. If the bar code matches, any one that is on the shelf will do."