Units mail

You're looking for information on units of mail!

In the United States, the United States Postal Service (USPS) uses the following units of mail:

1. Letter: A letter is a single piece of mail that weighs 1 ounce or less and is no larger than 11.5 inches long, 6.125 inches wide, and 0.25 inches thick.
2. Large Envelope: A large envelope is a single piece of mail that weighs more than 1 ounce but no more than 13 ounces, and is no larger than 12 inches long, 15 inches wide, and 0.75 inches thick.
3. Flat: A flat is a single piece of mail that weighs more than 13 ounces, and is no larger than 15 inches long, 23 inches wide, and 0.75 inches thick.
4. Package: A package is a single piece of mail that weighs more than 13 ounces and is larger than a flat.
5. Priority Mail: Priority Mail is a type of mail that is guaranteed to arrive within 1-3 business days, depending on the distance.
6. First-Class Mail: First-Class Mail is a type of mail that is used for personal correspondence and is typically delivered within 3-5 business days.
7. Standard Mail: Standard Mail is a type of mail that is used for bulk mailings and is typically delivered within 3-14 business days.

These are the main units of mail used by the USPS. Let me know if you have any other questions!