. The paper on the outside gives the sleeve stiffness which makes it easier to open and insert records. The poly lined inner surface lets the vinyl record slide with minimal friction which will reduce static electricity.
After cleaning an old or "new" second-hand record you should replace the inner sleeve. Cleaning the record and store it in an old dusty or even dirty inner sleeve is a waste of time.
We even recommend replacing the plain generic paper inner sleeves, with poly lined inner sleeves. The fact that sliding records in and out of these paper sleeves scratches records, creates static and paper dust.
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