This is one of the earlier USPS self-stick meter cuts that I have, dated February 9, 1993.

Note that instead of the required post office "city/state/zip code" it shows "UNIT CITY, ST 00000" Probably some post office hadn't programmed the new equipment correctly, but it does make for an interesting item, particularly since the label was postally used on a parcel.
Does anyone know when post offices first started using these type of labels for metered mail?