1. Introduction
This manual provides essential information for the safe and efficient operation of your NEREIDS NET 21V Cordless Grass Trimmer. Please read these instructions thoroughly before assembly, operation, or maintenance to ensure proper use and to prevent injury or damage.

Figure 1: Overview of the NEREIDS NET Cordless Grass Trimmer and included components.
2. Safety Information
Always prioritize safety when operating power tools. Failure to follow these safety guidelines may result in serious injury.
- Always wear appropriate safety gear, including eye protection and sturdy shoes.
- Keep a safe distance from others while operating the trimmer.
- Do not use the trimmer near flammable materials.
- Inspect the area for hidden objects (rocks, wires, etc.) before use.
- Keep hands and feet away from moving parts.
- Always unplug or remove the battery before performing maintenance or repairs.
- The cordless weed wacker brush cutter is equipped with a safety lock on the handle to prevent accidental starting.
- A weed splash guard is included to prevent debris from splashing during operation.
3. Package Contents
Verify that all items are present upon unpacking:
- 1 x Electric Lawn Mower unit
- 2 x 21V 2000mAh Batteries
- 1 x Charger
- 1 x Round Blade (for branches and shrubs)
- 2 x Stainless Steel Blades (for lawns, branches, and vines)
- 5 x Plastic Blades (for new growth/tender grass)
- 1 x Wheel Set
- 1 x User Manual (this document)
4. Setup
Follow these steps to assemble and prepare your grass trimmer for use.
4.1. Battery Charging and Installation
- Before first use, fully charge both 21V 2000mAh batteries using the provided charger. Charging time is approximately 2-3 hours per battery.
- Once charged, slide a battery into the designated slot on the trimmer's handle until it clicks securely into place.
4.2. Blade Installation
The trimmer supports three types of blades for various cutting tasks. Always ensure the trimmer is off and the battery is removed before changing blades.
- Remove the protective cover from the trimmer head.
- Select the appropriate blade for your task: plastic blades for tender grass, stainless steel blades for tougher weeds and small branches, or the round saw blade for thicker branches and shrubs.
- Align the chosen blade with the spindle on the trimmer head and secure it using the provided fasteners and tools. Ensure it is tightly fastened to prevent detachment during operation.

Figure 2: The three interchangeable blade types: circular saw blade, flat iron blade, and plastic blade.
4.3. Wheel Set Attachment
For mowing and easier maneuverability on flat surfaces, attach the wheel set:
- Locate the attachment points on the trimmer head's protective cover.
- Slide the wheel set onto these points and secure them with the provided knobs or clips. Ensure they are firmly attached.
4.4. Handle and Telescopic Rod Adjustment
Adjust the trimmer to a comfortable working height and angle:
- The telescopic rod can be adjusted from 88cm (34.6 inches) to 120cm (47.2 inches). Loosen the locking mechanism on the rod, extend or retract to the desired length, and then securely tighten the mechanism.
- Adjust the D-shaped handle position along the rod for optimal balance and control. Tighten its fastening knob once positioned.

Figure 3: The telescopic rod allows for adjustable length from 88cm to 120cm.
4.5. Head Angle Adjustment
The trimmer head angle can be adjusted to suit different trimming environments and reach difficult spots. Locate the head angle adjustment button and press it to change the angle, then release to lock it in place.
Video 1: Detailed instructions on how to install the various components of the grass trimmer, including blades, wheels, and adjusting the handle and head angle.
5. Operating Instructions
Ensure all safety precautions are followed before operating the trimmer.
5.1. Starting the Trimmer
- Ensure a charged battery is installed.
- Engage the safety lock on the handle.
- Press the power button while holding the safety lock to start the trimmer. Release the safety lock once the trimmer is running.
5.2. Trimming, Edging, and Mowing
- Trimming: Hold the trimmer at a comfortable angle, allowing the blade to cut through grass and weeds. Move steadily across the area.
- Edging: Adjust the trimmer head to a vertical position. Use the edge guide (if applicable) or the wheels for stability to create clean lines along sidewalks or flowerbeds.
- Mowing: With the wheel set attached and the head adjusted to a horizontal position, push the trimmer across the lawn like a small mower for even cutting.

Figure 4: The trimmer can be easily converted for edging, mowing, and general trimming tasks.
Video 2: Demonstration of the electric weed eater in action, showcasing its effectiveness in various garden scenarios.
6. Maintenance
Regular maintenance ensures the longevity and optimal performance of your trimmer. Always remove the battery before any maintenance.
- Cleaning: After each use, clean the trimmer head and protective guard to remove grass clippings and debris. Use a damp cloth; avoid harsh chemicals.
- Blade Inspection: Regularly inspect blades for wear, damage, or dullness. Replace worn or damaged blades immediately to maintain cutting efficiency and safety.
- Storage: Store the trimmer in a dry, secure location away from children and pets. Remove the battery if storing for extended periods.
7. Troubleshooting
If you encounter issues with your trimmer, refer to the following common solutions:
- Trimmer does not start: Ensure the battery is fully charged and properly installed. Check that the safety lock and power button are engaged correctly.
- Poor cutting performance: Inspect the blade for damage or dullness. Replace the blade if necessary. Ensure the correct blade type is used for the vegetation.
- Excessive vibration: Check that the blade is correctly installed and tightened. Ensure no debris is caught in the trimmer head.
8. Specifications
| Feature | Specification |
|---|---|
| Brand | NEREIDS NET |
| Model Number | 14072812 |
| Power Source | Battery Powered |
| Motor | 650W |
| No Load Speed | 18000 RPM |
| Battery | 21V 2000mAh Built-in Battery (x2) |
| Charging Time | Approximately 2-3 Hours Per Battery |
| Working Cutting Time | 30 to 60 Minutes |
| Cutting Diameter | 6 inch (150mm) |
| Adjustable Length | 88cm-120cm (34.6 Inches to 47.2 Inches) |
| Product Dimensions | 49"L x 6"W |
| Assembly Required | Yes |
9. Warranty and Support
For warranty information, technical support, or replacement parts, please contact NEREIDS NET customer service through your original purchase channel. Keep your purchase receipt and model number (14072812) handy for faster service.