Introduction
The Thermacell Portable Mosquito Repeller MR300 provides a 15-foot zone of protection against mosquitoes. This device is designed for outdoor use, offering a scent-free and mess-free solution for mosquito defense. It operates without cords or batteries, making it suitable for various outdoor activities.
Safety Information
- Keep away from children and pets.
- For outdoor use only. Do not use indoors, in tents, or in any enclosed area.
- Do not touch the repellent mat when the device is operating, as it will be hot.
- Do not cover the repeller while in use.
- Store in a cool, dry place when not in use.
- The repellent formula is inspired by natural plant extracts and is designed to be scent-free.

Image: The Thermacell Portable Mosquito Repeller is designed to be people and pet friendly when used as directed.
Package Contents
Your Thermacell Portable Mosquito Repeller MR300 package includes:
- 1 x Thermacell Portable Mosquito Repeller (MR300)
- 1 x 12-hour Fuel Cartridge
- 3 x 4-hour Repellent Mats

Image: The starter kit includes the repeller unit, one fuel cartridge, and three repellent mats.
Setup
Follow these steps to prepare your Thermacell repeller for use:
- Insert Repellent Mat: Remove one repellent mat from its packaging. Slide the mat into the opening beneath the grill on the top of the repeller. Ensure the mat is fully inserted.
- Insert Fuel Cartridge: Remove the cap from the fuel cartridge. Unscrew the bottom cover of the repeller. Insert the fuel cartridge into the opening, twisting it clockwise until it is fully seated. Replace the bottom cover.

Image: Visual guide for inserting the repellent mat and fuel cartridge into the device.
Operating Instructions
To activate the mosquito protection zone:
- Turn On: Slide the ON/OFF switch to the "ON" position.
- Activate Heat: Press the START button. You should see a small orange glow through the grill, indicating the heating element is active. If no glow is visible, press the START button several times.
- Placement: Place the repeller on a flat, stable surface in the area you wish to protect. For optimal results, allow 10-15 minutes for the 15-foot protection zone to establish.
- Turn Off: To turn off the device, slide the ON/OFF switch to the "OFF" position.
The Thermacell repeller uses heat-activated technology to disperse the mosquito repellent from the mat, creating a protective zone. This system is scent-free and does not require open flames or direct application to skin.

Image: The repeller establishes a 15-foot zone of protection, ideal for outdoor gatherings.
Maintenance
- Repellent Mat Replacement: Each repellent mat provides up to 4 hours of protection. The mat will turn from blue to white when it is exhausted and needs replacement. To replace, ensure the device is off and cool, then slide out the old mat and insert a new one.
- Fuel Cartridge Replacement: Each fuel cartridge provides up to 12 hours of operation. When the fuel runs out, the heating element will no longer glow orange. Replace the fuel cartridge as described in the "Setup" section.
- Cleaning: The repeller generally requires minimal cleaning. If necessary, wipe the exterior with a damp cloth. Do not immerse the device in water or use harsh chemicals.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No orange glow after pressing START. | Fuel cartridge is empty or not properly inserted. | Check if the fuel cartridge is empty and replace if needed. Ensure it is twisted in completely. Press START multiple times. |
| Mosquitoes are still present. | Repellent mat is exhausted, device is not on, or windy conditions. | Check if the mat has turned white and replace if necessary. Ensure the device is on and glowing. On windy days, place the repeller upwind of your location for better effect. Allow 10-15 minutes for the zone to establish. |
| Device does not turn on. | Fuel cartridge is empty or device malfunction. | Replace the fuel cartridge. If the issue persists, contact customer support. |
Specifications
| Feature | Detail |
|---|---|
| Model Number | MR300 |
| Brand | Thermacell |
| Protection Zone | 15 feet |
| Fuel Cartridge Life | 12 hours |
| Repellent Mat Life | 4 hours per mat |
| Scent | Scent Free |
| Item Weight | 6.4 ounces |
| Power Source | Butane Fuel Cartridge (no batteries required) |
Warranty and Support
The Thermacell Portable Mosquito Repeller MR300 comes with an automatic 1-year warranty. You can extend this warranty to 2 years by registering your product. Please refer to the product packaging for detailed registration instructions and warranty terms.
For technical support or further assistance, please visit the official Thermacell website or contact their customer service department.







