1952 Topps Packs - Mantle
 

It looks like PSA grades some pack with a Series 1 Designation and others with no designation.

Aren't they all Series 1 anyway, in terms of what PSA has graded?

Also, wasn't the Mantle card in both Series 1 and others?

Mantle #311 is the first card in the high numbers for the sixth and final series.