Use these convenient NetStamps Labels with your Stamps.com account for all your postage needs! NetStamps labels never expire, so print, peel, stick and go at your own pace! Have as many as you need ready on hand for routine mailing needs, and use them immediately or months later! Valid for use with domestic or international USPS First Class Mail, when mailing letters, postcards and flats or large envelopes. Netstamps have no date or domestic address restriction Note -- NetStamps are not authorized for use on Packages, Priority Mail or Priority Mail Express per USPS regulations Fluorescent watermarked, ensuring the security of your postage All NetStamps are proudly printed in the USA