Are PayPal labels considered USPS METERED mail or STAMPED mail?

[Temp20220914e]

Are PayPal labels considered METERED mail or STAMPED mail?  There are two different drop boxes at the USPS, and I'm not sure which one to drop a package in that has a PayPal printed label affixed.

[surplusdealdude]

Metered mail, but it doesn't really matter a lot - they're not going to refuse it if you drop it in the wrong slot.