Bonhams : Rolex. A fine and rare stainless steel automatic calendar dual time bracelet watch with bakelite bezel GMT Master, Ref 6542, Purchased 18th December 1957
Reference 6542 GMT-Master | A yellow gold automatic dual time zone wristwatch with date, bracelet, and bakelite bezel, Circa 1958 | 勞力士型號6542 GMT-Master 黃金自動上鏈兩地時間腕錶備日期顯示,配鍊帶及人造樹膠錶圈,製作年份約
Found: A Strange Rolex Document About The Famous GMT-Master Radioactivity Recall - Hodinkee