An automatic movement is fully mechanical and needs no battery. As you wear the watch, a weighted rotor inside spins with your wrist and winds the mainspring, and the mainspring powers the watch. Our automatic models use the 6T27, a caliber built for more compact watches. It has 21 jewels and beats at 28,800 vibrations per hour, which gives the seconds hand a smooth, sweeping motion instead of the tick of quartz. Fully wound, it runs for about 40 hours off the wrist. If it has stopped, turn the crown about 20 times to wind it, then set the time. Like every mechanical watch, it gains or loses a few seconds a day depending on how and how often it's worn.

Brew Automatic Watches are water resistant up to 10ATM (100 Meters) Do not swim or dive with your watch as they are not waterproof. The Brew Chronograph models are rated up to 5ATM (50 Meters). Please ensure that you rinse your watch with distilled or tap water after exposure to salt or pool water to rinse off any salt-water or chlorine that can be corrosive to the watch gaskets. Refrain from wearing your Brew watch in hot tubs, showers and saunas as the various components used in the manufacture and assembly of your watch expand at various rates. The rapid change in temperature when entering a hot tub can result in a loss of the sealing capabilities of gaskets, which may allow moisture to enter.