They are made for the Rolex 380B Oyster watch band # 93150 5512, 5513, 1665, 1680 watch which takes spring bars for the 20mm end piece. 17MM 18MM 19MM 20MM 21MM 22MM 23MM 24MM 26MM. 455B END PIECE FIT OYSTER BAND ROLEX SUBMARINER 16800 SHINY CTR FAT SPRING BAR.
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