Fits for Most Rolex Watch Model Collection: 16610, 16613, 16618, 16700, 16710, 16713, 16718, 16760, 16800, 16803, 16808. Size Options: 38 MM For 40 MM Watch. Material: Ceramic. 38 X 30.7 X 1.6 MM. These inserts are made with ceramic and easy to break.
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