At the Post Office they have a plastic template with a slot cut into it. If your envelope can pass through the slot and bends easily (No Toploaders) then it needs $0.45 in postage. If it is too thick to go through the slot or it won't bend easily it will jam their automatic sorting machines. Therefore it is classified as non-machinable and requires a $0.20 surcharge. This is why there is so many horror stories about people using a PWM and receiving an empty envelope. The machine jams and the envelope gets ripped up because it won't bend around the corners in the machine.
As for the other question, If you send as a First Class Mail/Parcel as a Package or Thick envelope (PayPal Shipping $1.64) there is a minimum thickness of 3/4". A toploader and several cards in a bubble mailer is less than 3/4" so I wrap some extra bubble wrap around it to thicken it up.
Ray
As for the other question, If you send as a First Class Mail/Parcel as a Package or Thick envelope (PayPal Shipping $1.64) there is a minimum thickness of 3/4". A toploader and several cards in a bubble mailer is less than 3/4" so I wrap some extra bubble wrap around it to thicken it up.
Ray
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