Gizmodo has obtained what appears to be full marketing materials for two new Fitbit activity trackers — the Charge and Charge HR — ahead of each device’s respective release. Based on the leak, it appears that the two new wearables will have some interesting features like caller ID and heart rate monitoring that could be paired with an iPhone.

First and foremost, the Fitbit Charge appears to be an improved iteration of the Fitbit Force that was recalled last year after the company received user complaints of skin rashes and burns. The design of the Charge is very similar to the Force, with a full display and wider band that appears to be more durable than the similar-looking Fitbit Flex.

The claimed features of the Fitbit Charge:

• Tracks steps, distance, calories burned, floors climbed, & active minutes
• Displays stats, time, & caller ID
• Monitors sleep quality
• Silent, vibrating alarm
• Water resistant

Most of the feature set listed above is what you would expect from a Fitbit device, although caller ID could prove useful for Fitbit users that pair the tracker with an iPhone. Presumably, when you receive an incoming call on your iPhone, the Fitbit Charge will display the name and number of who is calling on your wrist for the added convenience.

The more interesting device is the Charge HR, which has the same features as the Charge plus the incorporation of heart rate monitoring functionality. Again, since Fitbit devices can be paired with an iPhone, this creates a possible alternative to the Apple Watch for iPhone users that are looking for continuous heart rate monitoring through a wearable.

The Charge HR displays 24-hour information about your heart rate on the same ticker as the time and other fitness information is shown on the tracker. A number of patent applications also suggested that Fitbit was planning to add navigation and weather-tracking functionality to the devices, but those features do not appear to have materialized.

The claimed features of the Fitbit Charge HR:

• PurePulse continuous, wrist-based heart rate for better calorie tracking & cardio training
• Tracks steps, distance, calories burned, floors climbed, active minutes & 24/7 heart rate
• Use with MobileRun on the Fitbit App to see run stats
• Displays activity + run stats, time, & caller ID
• Monitors sleep quality
• Silent, vibrating alarm
• Water resistant

The exact pricing and availability information for the Charge and Charge HR remains unknown.

Fitbit did not immediately respond to request for comment.