Hart rate monitor Garmin HRM DUAL with a chest belt is comparable to HRM Premium when it comes to the construction, but on top of the ANT+ wireless communication it also supports Bluetooth Low Energy signal. While the ANT+ communication can be used primarily to connect with Garmin sporttesters, Bluetooth Low Energy signal is suitable for wide range of electronic devices such as smartphones, smartwatches from other brands, or fitness equipment like treadmill, indoor bicycles, or indoor rowing machines.