Introduction
This manual provides essential information for the safe and efficient use of your XO Z66 Ultra Smartwatch. Please read it thoroughly before using the device to ensure proper operation and to understand all features.
1. Setup
1.1 Unboxing and Package Contents
Verify that all items are present in the package:
- 1x XO Z66 Ultra Smartwatch
- 1x Watch Strap
- 1x Silicone Strap
- 1x Charger
- 1x User Manual (this document)

Image: The XO Z66 Ultra Smartwatch, featuring a silver-colored case and a black wavy-textured strap, displayed from an angled perspective showing the watch face and side buttons.

Image: A black silicone watch strap with multiple perforations, designed for comfort and adjustability.
1.2 Initial Charging
Before first use, fully charge your smartwatch. Connect the provided charger to a power source and place the smartwatch on the charging base. The watch supports wireless fast charging.
A full charge typically takes approximately 2 hours. The battery indicator on the watch display will show charging status.

Image: The rear view of the XO Z66 Ultra Smartwatch, highlighting the optical sensors for health monitoring and the wireless charging contact points on the back of the silver-colored case.
1.3 App Installation and Pairing
- Download the MasWear application from your smartphone's app store (iOS App Store or Android Google Play Store).
- Ensure Bluetooth is enabled on your smartphone.
- Open the MasWear app and follow the on-screen instructions to create an account or log in.
- In the app, select "Add Device" or similar option and choose your XO Z66 Ultra Smartwatch from the list of available devices.
- Confirm the pairing request on both your smartphone and the smartwatch.
2. Operating Instructions
2.1 Basic Controls
The smartwatch features a full touch screen, a switch button, and a function button for navigation and interaction.
- Touch Screen: Swipe left, right, up, or down to navigate menus and tap to select options.
- Switch Button: Typically used for power on/off, returning to the home screen, or accessing the app menu.
- Function Button: Customizable for quick access to specific features like sports modes or health tracking.

Image: A close-up view of the XO Z66 Ultra Smartwatch display, showing a detailed watch face with various data points like time, date, compass, and activity metrics.
2.2 Key Features
- Display: The 1.99-inch 320*385 TFT display offers a clear and bright interface for viewing information.
- NFC Capabilities: The smartwatch supports NFC for various functions, including simulating company/community access control cards. Refer to the MasWear app for setup.
- Water Resistance: With an IP67 rating, the watch is life waterproof, meaning it can withstand splashes, rain, and brief immersion. It is not suitable for swimming or diving.
- Customizable Dials: Choose from a variety of built-in watch faces or customize your own through the MasWear app to match your style and mood.
- Sports and Health Tracking: Monitor multiple sports indicators and health metrics directly from your wrist.
3. Maintenance
3.1 Cleaning Your Smartwatch
To maintain the appearance and functionality of your smartwatch:
- Wipe the screen and case with a soft, lint-free cloth.
- For stubborn dirt, slightly dampen the cloth with water. Avoid using harsh chemicals or abrasive materials.
- Clean the charging contacts and sensors on the back of the watch regularly to ensure proper charging and accurate readings.
3.2 Water Resistance Precautions
While the watch is IP67 life waterproof, observe the following:
- Do not expose the watch to hot water, steam, or high-pressure water jets.
- Avoid using the watch in saunas or steam rooms.
- If the watch gets wet, dry it thoroughly before charging or operating buttons.
- The water resistance may decrease over time with normal wear and tear.
4. Troubleshooting
If you encounter issues with your XO Z66 Ultra Smartwatch, try the following solutions:
- Watch not turning on: Ensure the watch is fully charged. Connect it to the charger for at least 30 minutes.
- Cannot pair with smartphone:
- Ensure Bluetooth is enabled on your phone and the watch.
- Restart both your phone and the smartwatch.
- Make sure the MasWear app is updated to the latest version.
- If previously paired, try unpairing and re-pairing the device through the MasWear app and your phone's Bluetooth settings.
- Inaccurate health data: Ensure the watch is worn snugly on your wrist, not too tight or too loose. Clean the sensors regularly.
- Charging issues: Check if the charger is properly connected and the charging contacts on the watch are clean and free of debris.
For further assistance, refer to the MasWear app's help section or the manufacturer's official support channels.
5. Specifications
| Feature | Detail |
|---|---|
| Model Name | Ultra 8 (S8) |
| Brand | XO |
| Display Type | TFT |
| Screen Size | 1.99 Inches (320*385 resolution) |
| Case Material | Titanium alloy |
| Case Size | 49mm |
| Operation Method | Full touch + switch button + function button |
| Companion App | MasWear |
| Water Resistance | IP67 (Life Waterproof) |
| Connectivity | Bluetooth, NFC |
| Operating System | Android Wear |
| Memory Storage | 128 MB |
| Battery | Built-in rechargeable (Wireless Fast Charging) |
| Product Dimensions (Package) | 40 x 20 x 20 cm; 120 g |
6. Warranty and Support
Warranty information for the XO Z66 Ultra Smartwatch is typically provided at the point of purchase or included with the product packaging. Please retain your proof of purchase for warranty claims.
For technical support, troubleshooting beyond this manual, or warranty inquiries, please contact your retailer or visit the official XO brand website for customer service contact details.