Rolex GMT-MasterFasten your seatbelts for the story of the Rolex GMT-Master. Aviation company Pan-Am requested Rolex to create a wristwatch that would display multiple time-zones simultaneously, as their flights got longer; crossing multiple time-zones. Rolex came up with the GMT-Master (‘GMT’ stands for ‘Greenwich Mean Time’) in 1954. The watch features a date-function and an extra hour hand (with triangle) that points out the second time zone on the bi-directional turning, 24hour bezel.Still linked to aviation and although meant for professional use, it enjoys a much wider fan base ever since it first saw light. Over the years it underwent some changes and there are so many wonderful variations of this all-time Rolex classic. Some GMT’s are great as a single purchase, others are a wonderful addition to any collection and some of them can be considered as the crowning glory.Reference 1675Introduced in 1959 and with a very long production of more than 20 years: the 1675! On this model they added the ‘Pointed Crown Guards’ (PCG) a.k.a. ‘Cornino'. These crown guards got replaced by regular rounded crown guards in 1964/1965. The dial also underwent some changes: from glossy gilt chapterring to a matte radial dial in the end with lots of variations in between, like the rare ‘Exclamation Mark’, ‘Underline’ and ‘Double Swiss’ dials. The red GMT-hand changed as well because the small arrow was replaced by a bigger one. The 1675 was mainly produced in steel but was also available in 18k yellow gold or a combination of both materials.PepsiThe red/ blue bezel inserts on the steel GMT’s are referred to as ‘Pepsi bezels’ as it assembles the same colours, but in fact Rolex chose this combination because of the Pan-Am colours. The heritage of the Pepsi bezel starts in 1959, when the rare bakelite bezels were used. Up until 2007 aluminium Pepsi bezels were used (optional, next to an all-black or black/red a.k.a. ‘Coke bezel’). After being discontinued for 7 years, Rolex relaunched the beloved ‘Pepsi bezel', yet this time made out of Cerachrom and only available on the white-gold model. At 2018 Baselworld Watch Fair, Rolex introduced the stainless steel Pepsi with Jubilee bracelet.