FeaturesComfortable, elastic fabric strap to minimize chance of chaffing; strap can be hand washedAccurate and reliable; records data even when receiver communication is interruptedTwo-snap connection is easy and fast and includes adjustable length strapSends and receives signals up to 10 feet unobstructedCompatible with any ANT+ receiving deviceTracks heart rate, time spent in each heart rate zone, max heart rate, average heart rate, and calories burned while you work outWorks with the most popular running, cycling and fitness Apps such as Runmeter, RunKeeper, Cyclemeter, Strava, MapMyRun, Endomondo, Runtastic, Wahoo Fitness (included) and dozens moreData is sent right to your iPhone when paired with the required ANT+ Key/Adapter for iPhone (Wahoo Key for iPhone not included)Comfortable, elastic fabric strap to minimize chance of chaffing; strap can be hand washedAccurate and reliable; records data even when receiver communication is interrupted