Microprinting is one of the best ways to tell the genuine from the counterfeit. USPS does not use genuine fonts (though this one is the closest to a genuine font that I have seen) in their tagging while the fake ones always do.

Need an order expedited? Expedited Shipping Options are available. Priority Mail (1-3 days, but not guaranteed) & Priority Mail Express (1-2 days guaranteed) & FedEx (1 day guaranteed) is available for orders. Message me on it and I will respond immediately and give you a quote (8 am - 10 pm EST). My intention on all expedited orders is to have the order in the hands of the shipper immediately. I have Priority Mail & Priority Mail Express stamps in stock and can have a cancelled one on your package (guaranteed genuine - no fakes - see my Priority Mail & Express listings for details on the fakes) if you would like one.