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. features:tap on lens ' for toggling through your favorite modessleek design ' smaller and less bulky with lie flat designcomfort band ' soft silicone strap with aeration for maximum comforteasy-to-read display ' better quality lcd with larger charactersdigital time & calendar