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1/1 1969 Topps #220 Sam McDowell (Cleveland Indians) states UNIQUE PROOF-8 and 1989 TOPPS AUCTION ASA84414 - by ASA Accugrade
1969 Topps Sam McDowell #220 (Unique Proof-8)

Provenance: The label explicitly states "1989 TOPPS AUCTION," identifying it as a file copy from the Topps archives.
Significance: The "Unique" designation usually refers to a specific production stage (such as a progressive proof or a final file copy) that was the only one of its kind available in that 1989 sale.

1/1 1975 O-Pee-Chee (OPC) #645 Danny Cater (Boston Red Sox) by ASA
1975 Topps Danny Cater #645 (Test Proof)

Type: This is a "Blank Back" test proof. You can see in the second image that the reverse is unfinished cardboard.
Significance: These were used by Topps to check image centering and color before the full production run. Like the McDowell, this likely originated from the same 1989 archive sale.