Introduction
Thank you for choosing the BLACK+DECKER 20V MAX 12 Inch Cordless String Trimmer and Wheeled Edger. This versatile tool is designed for efficient lawn care, offering both trimming and edging capabilities. Its cordless design provides freedom of movement, while advanced features ensure optimal performance.
Key features include:
- Automatic Line Advancement (AFS): Effortlessly dispenses trimmer line for uninterrupted operation.
- Extended Battery Capacity: The LBXR2520 battery provides extended runtime for larger projects.
- Dual Speed Control: Allows selection between higher power for tough areas or longer runtime for extended tasks.
- PowerDrive Transmission: Boosts torque at the string for enhanced cutting power against dense growth.
- Effortless Conversion: Quickly transforms from a string trimmer to a wheeled edger.
- Adjustable Comfort: Customizable height and handle settings with a premium soft grip for improved control.

Figure 1: BLACK+DECKER LST522 Cordless String Trimmer and Wheeled Edger.
Included Components
Your BLACK+DECKER LST522 kit includes the following items:
- LST522 20V MAX* cordless trimmer/edger
- LBXR2520 20V MAX* extended runtime lithium battery
- Charger
- AFS spool
- Guard

Figure 2: Annotated diagram highlighting key features and components of the LST522.
Setup
1. Assembly
Attach the guard to the trimmer head following the instructions in the included manual. Ensure it is securely fastened before use. Adjust the auxiliary handle and shaft height to a comfortable operating position. The premium soft grip handle can be adjusted for optimal control.
2. Battery Charging
The LBXR2520 20V MAX* lithium battery must be fully charged before first use. Insert the battery into the charger, ensuring proper alignment. The charger indicator light will show the charging status. Once fully charged, remove the battery from the charger. Always use the BLACK+DECKER charger provided with your tool.

Figure 3: The 20V MAX* battery system is compatible with a wide range of BLACK+DECKER tools.
Operating Instructions
1. Trimming
Hold the trimmer firmly with both hands. To start, press the safety lock-off button and then squeeze the trigger. Move the trimmer in a sweeping motion, keeping the cutting line parallel to the ground. The Automatic Feed Spool (AFS) system will automatically advance the line as needed, providing uninterrupted performance.

Figure 4: Trimming grass with the LST522.
2. Wheeled Edging
To convert the tool to a wheeled edger, simply rotate the shaft. The integrated wheel allows for precise and clean lines along sidewalks and driveways. Guide the wheel along the edge of the surface you wish to trim, maintaining a steady pace.

Figure 5: The LST522 easily converts to a wheeled edger for precise lines.
3. Dual Speed Control
The LST522 features dual speed control. Use the higher speed setting for tougher overgrowth and dense areas, leveraging the PowerDrive Transmission for increased torque. Switch to the lower speed setting for lighter tasks or to extend battery runtime.

Figure 6: Adjusting the dual speed control for optimal performance or runtime.
4. Automatic Line Advancement (AFS)
The AFS system eliminates the need for manual bumping to advance the line. It automatically feeds the trimmer line as you work, ensuring continuous cutting without interruption.

Figure 7: The AFS system ensures continuous line feed without manual intervention.
Maintenance
1. Spool Replacement
When the trimmer line runs out, replace the AFS spool with a new one. Refer to the detailed instructions in your product manual for the correct procedure to remove the old spool and install a new one. Ensure the tool is disconnected from the battery before performing any maintenance.
2. General Care
Keep the tool clean and free of debris. Regularly inspect the cutting line and guard for any damage. Store the trimmer in a dry, secure location away from children and pets.
Troubleshooting
If your trimmer/edger is not operating as expected, consider the following common issues:
- Tool not starting: Ensure the battery is fully charged and properly inserted. Check that the safety lock-off button is pressed before squeezing the trigger.
- Line not advancing: Verify that the AFS spool is correctly installed and that there is sufficient line remaining.
- Reduced cutting performance: The cutting line may be worn or too short. Replace the spool if necessary. Ensure the tool is operating in the appropriate speed setting for the task.
For more detailed troubleshooting, please refer to the complete instruction manual or contact BLACK+DECKER customer support.
Specifications
| Feature | Specification |
|---|---|
| Brand | BLACK+DECKER |
| Model Number | LST522 |
| Power Source | Battery Powered (20V MAX Lithium Ion) |
| Item Weight | 5.7 Pounds |
| Cutting Width | 12 Inches |
| Product Dimensions | 41.33"L x 9.25"W |
| Speed | 100 RPM (Dual Speed Control) |
| Batteries Required | 1 Lithium Ion battery (included) |
| UPC | 885911450447 |
Safety Information
Always prioritize safety when operating power tools. Follow these guidelines:
- Always wear eye protection, long pants, closed-toe shoes, and hearing protection.
- Keep bystanders and pets at a safe distance from the operating area.
- Do not operate the trimmer if you are tired or under the influence of drugs or alcohol.
- Ensure the battery is removed when not in use or when performing maintenance.
- Inspect the tool for any damage before each use.
Warranty and Support
The BLACK+DECKER LST522 20V MAX 12 Inch Cordless String Trimmer and Wheeled Edger comes with a 2-Year limited warranty. For warranty claims, technical support, or replacement parts, please refer to the contact information provided in your product packaging or visit the official BLACK+DECKER website.





