Fitbit’s newly announced $150 Charge HR and $250 Surge devices are now available for purchase, the company has announced.

The former is an upgraded version of the already-available Charge smart band with an added heart rate monitor, while the latter is a smart watch, or as Fitbit likes to call it – a “superwatch.”

The Surge is obviously more impressive of the two devices as it goes beyond fitness-based features to include enhanced notifications to the mix, alerting users on incoming calls, texts, emails, tweets and more. In addition, it integrates more sensors such as a GPS, compass and altimeter and can work even without a connected smartphone.

Both devices can keep up with one’s activity and sleep, in addition to monitoring user’s heart beats.