A quartz movement works by being charged by a battery causing a quartz crystal to oscillate. The output of the oscillator is then converted to pulses suitable for the digital circuits in the watch which in turn create 1-second pulses that drive a tiny electric motor which is connected to standard gears to drive the hands. A quartz watch doesn't need to be wound and works without intervention - until the battery dies - which is typically two or three years after purchase. All quartz watches purchased from Stewart’s will receive their 1st battery change free of charge. Brands such as Defakto go to great efforts to manufacture hard wearing and ultra accurate quartz movements.