Dead Letter Office, Small Format Forwarding Seals, Types 1-11 Complete. Complete collection of these labels mounted on 5 exhibit pages comprising the eight different designs with a total of eleven different listings (three with different perfs), better includes #OXA2 on reverse of Grant Letter Sheet (U293), the only recorded example of DLO seal on such; a Very Fine collection. Scott No. OXA1A/OXA9  Estimate $1,500 - 2,000. The forwarding seals were applied on the back of envelopes for which the Dead Letter Office was able to determine a correct address. The corrected address is always on the front in red ink. $0 (Image)