Top features:- Bone conducting headphones leave your ears free to hear ambient sound- Lightweight headband with IP55 sweat resistance- Built-in microphone so you can take calls on-the-goBone conductingThe Aftershokz Trekz Titanium Wireless Bluetooth Headphones utilise bone conducting technology to deliver your favourite audio without needing in-ear buds.This means your ears are left open to ambient noise so you're always aware of what's going on around you, so you can stay safe while out on your runs.Lightweight headbandWith a lightweight headband, the AS600S Trekz Titanium are comfortable to wear for long periods while you exercise.They are also IP55 certified for sweat, dust, and moisture repellence, so you don't have to worry when you push yourself to the limit.Built-in microphoneIf you need to take a call while you're on the go, the headphones have built-in microphones for your convenience.They have noise-cancelling capabilities, so the caller will be able to hear you in clarity, wherever you might be.