# Identifiers
Peach objects always have unique identifiers created by Peach. Some objects support external IDs. If external ID is supported, the object will have `externalId` attribute. You can fetch objects using external ID (only objects that support external IDs).
Peach IDs have the same format XX-YYYY-YYYY.
XX - is a prefix from the list below.
YYYY-YYYY - is a random set of numbers and letters (capital characters A-Z and digits 1-9). The digit zero is not used to avoid confusion with capital letter O.