(a) 9 Pieces of 4" / 100mm (5/8"-11 Female Thread arbor) Aluminum Backer / Pad holder for diamond polishing pad. This 19 Pieces of aluminum backer's arbor is 5/8"-11 Female Thread. (b) 9 Pieces of 5" / 125mm (5/8"-11 Female Thread arbor) Aluminum Backer / Pad holder for diamond polishing pad.
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