Online Exclusive: shop.ballwatch.ch/rmtmt The new Roadmaster TMT with the patented mechanical thermometer is a bright testimony of our pioneering spirit and craftsmanship. Available in 40mm and 43mm cases, the Roadmaster TMT measures ambient temperature between -31°F and 113°F, or -35°C and 45°C, with 99% accuracy. Equipped with a specially blended movement oil that ensures flawless operation even in –40°C (-40°F) temperatures, while micro gas tubes shine on the dial and on the aluminum bezel in