They are stamps with a generic value. You buy them at the current rate of postage and if a first class letter rate goes up, they honor them on letters without having to add additional postage to pay the higher cost. We used to have to add extra two or four cent stamps to letters when postage went up. Forever stamps put a stop to this....thanks for asking....
Yes, there should show a GIN set. It's set at 20,000, but I'll double check. I have three Listia stickers set for the GIN and one Listia sticker with the regular bid/ But if the GIN isn't working I'll honor the credit level anyway and send out that many stickers.
Thank you....It's a bit of a bother to wait, so if you need them in a hurry, the best bet is still the local Post Office. But it helps when you can't get there.