Introduction
The YUNZII ACTTO B303 is a wireless Bluetooth keyboard designed with a retro typewriter aesthetic, combining vintage charm with modern functionality. Its compact 84-key layout, comfortable round keycaps, and multi-device compatibility make it suitable for various computing environments. This manual provides essential information for setting up, operating, and maintaining your B303 keyboard.

YUNZII ACTTO B303 keyboard in Midnight Navy, top-down view.
Package Contents
Please check the package for the following items:
- 1 x YUNZII ACTTO B303 Retro Wireless Keyboard
- 1 x User Manual
- 2 x AAA Batteries
- 1 x Extra Red Keycap

Contents of the product package: Keyboard, manual, AAA batteries, and an extra keycap.
Specifications
| Feature | Description |
|---|---|
| Product Model | YUNZII ACTTO B303 |
| Keyboard Type | Membrane Keyboard |
| Layout | 75% Layout, 84-Key |
| Backlight Type | No backlight |
| Keycap Material | ABS Plastic |
| Keycap Printing | Laser |
| Color Choices | Midnight Navy, Baby Pink, Ivory Butter, Snow White, Sweet Mint |
| Battery | Uses 2x AAA Batteries (included) |
| Connection | Bluetooth 5.0 |
| Wireless Range | Up to 10 meters (33 feet) |
| Dimensions (L*W*H) | 356mm * 218mm * 67mm (14 x 8.6 x 2.6 inches) |
| Weight | 1.15 kg |
| Hot Swappable | No |
| Integrated Stand | 12.9 inches long, 0.59 inches wide |
| Compatibility | Windows, Android, iOS (Mac, PC, Laptop, Tablet, Smartphone) |
| Certifications | CE, FCC, RoHS, KC, WEEE |

Keyboard dimensions and integrated holder for devices.
Setup
Bluetooth Connection Steps
Follow these steps to connect your YUNZII ACTTO B303 keyboard to your device:
- Select Operating System Profile: Press
Fn + 1for Android,Fn + 2for Windows, orFn + 3for iOS. This selects the correct key mapping for your device's operating system. - Initiate Pairing Mode: Long press
Fn + Kuntil the LED indicator on the right side of the keyboard begins to shine, indicating it is in pairing mode. - Connect on Your Device: On your computer, tablet, or smartphone, go to your Bluetooth settings and search for available devices. Select 'YUNZII B303' (or similar name) from the list.
- Enter Password (if prompted): If your device displays a password, type it on the B303 keyboard and press the
Enterkey to complete the pairing process. - Confirm OS Profile: After successful pairing, press
Fn + 1(Android),Fn + 2(Windows), orFn + 3(iOS) again to ensure the keyboard is correctly configured for your operating system.

Visual guide for Bluetooth connection steps.
Operating Instructions
Multi-Device Switching
The B303 keyboard allows you to connect to and switch between up to three different devices. Once paired, simply press Fn + 1, Fn + 2, or Fn + 3 to switch to the corresponding device profile.
Intelligent Auto Sleep
To conserve battery life, the keyboard features an intelligent auto-sleep function. If there is no activity for 20 minutes, the keyboard will automatically enter sleep mode. To wake it up, simply press any key.

Intelligent Auto Sleep feature for battery conservation.
Function Hotkeys
The keyboard includes 12 easy-to-reach function hotkeys (Fn + F1-F12) that provide shortcuts to various multi-functions. Refer to the keycap legends for specific functions.
Adjustable Tilt Legs
For enhanced ergonomic comfort during long typing sessions, the keyboard is equipped with two-stage adjustable tilt legs. Adjust them to your preferred angle.

Two-stage adjustable tilt legs for ergonomic typing.
Maintenance
Cleaning
To clean your keyboard, gently wipe the surface with a soft, dry, or slightly damp cloth. Avoid using harsh chemicals, abrasive cleaners, or excessive moisture, as these can damage the keycaps or internal components.
Battery Replacement
The YUNZII ACTTO B303 uses 2 AAA batteries. When the keyboard's performance degrades or it fails to connect, it's likely time to replace the batteries. Open the battery compartment, remove the old batteries, and insert new AAA batteries, ensuring correct polarity.
Troubleshooting
- Keyboard not connecting via Bluetooth:
- Ensure the keyboard has fresh batteries or sufficient power.
- Verify that Bluetooth is enabled on your device.
- Re-initiate pairing mode on the keyboard (
Fn + Klong press) and re-scan for devices on your computer/tablet/phone. - Ensure you have selected the correct operating system profile (
Fn + 1/2/3).
- Keys not responding:
- Check battery levels and replace if necessary.
- If the keyboard is in auto-sleep mode, press any key to wake it up.
- Try re-pairing the keyboard with your device.
- Lag or intermittent connection:
- Ensure your device is within the 10-meter (33 feet) wireless range.
- Minimize interference from other wireless devices.
- Ensure your device's Bluetooth drivers are up to date.
User Tips
- Language Layouts: The YUNZII ACTTO B303 keyboard features an English layout. If you require typing in other languages (e.g., Portuguese, Spanish with 'Ñ'), you can configure your operating system's input settings to match your desired language. For visual reference, consider using keycap stickers or referring to an on-screen keyboard.
- Integrated Stand: Utilize the integrated stand holder for your tablet or smartphone to create a comfortable and organized workspace, especially when typing on the go.
- Ergonomics: Take advantage of the adjustable tilt legs to find the most comfortable typing angle, reducing strain during extended use.
Warranty & Support
For warranty information and technical support, please refer to the documentation provided at the time of purchase or contact the seller directly. Keep your proof of purchase for any warranty claims.





