Polar A370 is a sleek fitness tracker with continuous wrist-based heart rate. Tracks daily steps, distance and calories burned. Polar Sleep Plus; analysis follows sleeping patterns and provides feedback. Use your phones GPS to track speed & distance. 24/7 companion with continuous heart rate tracking and a detailed overview of your daily activity. Polar sleep plus; tracks your sleep and gives you valuable sleep insights. The polar a370 is water-resistant and tracks pace, distance and route with your phones GPS. The polar a370 can be customised to match any style with changeable wristbands. Polar smart coaching features & polar flow web service. Size H22, W2.35, . Manufacturers 2 year guarantee.