Longines Master Longines Master Collection is comprised of notable timepieces known for their functionality, style and precision. Launched in 2005, Longines Master has quite a list of models in polished steel, yellow and pink gold, white and black dials in varied sizes from 25.50mm to 47.50mm. The collection has scratch-resistant sapphire crystal with transparent case back. The movement is largely self-winding chronograph with calibers such as L698, L697, L678, L651, L642, L635, L607 andL696 to name a few. General watch functions are hours, minutes, seconds and date with some models with GMT with inner 24 hours disc and ring with time zones, moon phase display and so on. Power reserve is from 38 to 56 hours, depending on the model.