Ebay introduced the new "Ebay delivery services" few months ago. This system offers cheap shipping for small item with 3 Oz or less. One of the biggest concerns on this new toll is that USPS staff cannot scan the labels, similar to First Class Mail packages. Also, you cant scan the label at stamp vending machine in local post office. So you are under the mercy of USPS. and hope that label is scanned while item is being mailed to buyers address. If it doesn't show in the system, your ebay sellers performance will be affected because they will mark as unverified shipping. It is a great shipping system that offers low cost shipping with tracking number. On ether other hand, it is a broken system because they cant give you a receipt when USPS receives the item.
