For the most effective workout, and maximum calories burned. The Zone Trainer 3.0 allows for continuous heart rate monitoring to accurately measure the effectiveness of your workouts. A stylish design with silicone strap is designed for the ultimate in both comfort and fashion, and a fabric chest strap can wirelessly transmit continuous heart rate data to your easy-to- read watch display. Now, tracking your workout has never been easier, or more pleasant to look at. Tap on Lens - for toggling through your favorite modes. Sleek Design, smaller and less bulky with lie flat design. Comfort Band, soft silicone strap with aeration for maximum comfort. Easy-to-read display, better quality LCD with larger characters. Digital time and calendar.