SAPPHIRE WATCH CRYSTAL FOR 42MM ROLEX EXPLORER II REF: 216570 YACHTMASTER 116655. SAPPHIRE WATCH CRYSTAL FOR ROLEX SUBMARINER NO DATE # 25-19 6538 6540 7928 7016. Sapphire Crystals. Now you can convert the plastic to a scratch resistant sapphire crystal and you will not have to change the crystal as long as you own the watch.
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