1. Introduction
This manual provides essential information for the safe and effective operation of your RDINSCOS MT-28 Pinless Moisture Meter. This non-invasive digital detector is designed to quickly and accurately measure moisture levels in various materials such as drywall, wood, tile, and masonry, up to a depth of 19mm, without causing damage to surfaces.

2. Safety Information
- Keep the device dry. Do not expose to water or excessive humidity.
- Avoid contact with metal surfaces during testing to ensure accurate readings.
- Do not attempt to disassemble or modify the device.
- Store in a cool, dry place away from direct sunlight and extreme temperatures.
- Keep out of reach of children.
3. Product Overview
The RDINSCOS MT-28 Pinless Moisture Meter is equipped with a large LCD display, mode selection buttons, a hold function, and an integrated flashlight. Its non-invasive sensor allows for quick and damage-free moisture detection.

4. Setup
4.1 Battery Installation
- Locate the battery compartment on the back of the meter.
- Open the battery compartment cover.
- Insert the included 9V battery, ensuring correct polarity.
- Close the battery compartment cover securely.
5. Operating Instructions
5.1 Powering On/Off
Press the power button (green button) to turn the meter on. Press and hold the power button to turn it off.
5.2 Mode Selection
The MT-28 offers multiple modes for different materials. Press the "MODE" button to cycle through the available options:
- Wall Mode: For drywall and similar wall materials.
- Masonry Mode: For brick, concrete, and other masonry surfaces.
- Soft Wood Mode: For softer wood types.
- Hard Wood Mode: For denser wood types.
Selecting the correct mode ensures accurate readings for the material being tested.
5.3 Taking Measurements
- Select the appropriate material mode using the "MODE" button.
- Place the back of the meter flat against the surface you wish to measure. Ensure your fingers are on the rubber grips and not on the sensor area to avoid inaccurate readings.
- The moisture percentage will be displayed on the LCD screen.
- Press the "HOLD" button to freeze the current reading on the display. Press it again to release.
- Use the integrated flashlight (button with flashlight icon) for measurements in dimly lit areas.
Important Note: For optimal accuracy, avoid placing the meter directly over metal objects or pipes within the wall, as this can interfere with the readings.




5.4 Interpreting Readings
The meter provides a percentage reading and visual indicators (DRY, MID, WET) to help interpret moisture levels.

6. Maintenance
- Cleaning: Wipe the device with a soft, dry cloth. Do not use abrasive cleaners or solvents.
- Storage: When not in use, store the meter in its provided storage bag in a cool, dry place.
- Battery Replacement: Replace batteries when the low battery indicator appears on the display to ensure continued accurate operation.
7. Troubleshooting
If you encounter issues with your MT-28 moisture meter, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Inaccurate Readings | Contact with metal objects | Avoid testing over metal pipes or studs. |
| Inaccurate Readings | Uneven surface | Ensure the meter is placed flat and flush against the surface. |
| No Display/Power | Dead batteries | Replace the 9V battery. |
| Readings are "Relative" | Pinless meters provide relative values | Understand that readings are comparative, not absolute moisture content. Different materials and densities affect values. |
For further assistance, please contact customer support.
8. Specifications
| Feature | Specification |
|---|---|
| Manufacturer | SHENZHEN REDDRAGON INSTRUMENTS CO.,LTD |
| Part Number | MT18 |
| Item Weight | 8.4 ounces |
| Package Dimensions | 6.61 x 3.27 x 1.65 inches |
| Item Model Number | MT-28 |
| Batteries | 2 AAA batteries required (included) |
| Color | Red-green |
| Power Source | Battery Powered |
| Included Components | 1*Wood Moisture Meter; battery |
| Battery Cell Type | Alkaline |
| ASIN | B0FCLCZFVG |
| Date First Available | May 25, 2020 |
9. Warranty and Support
RDINSCOS is committed to providing reliable tools. For any product inquiries, technical support, or warranty claims, please contact our customer service team.
Visit the official RDINSCOS Store for more information and support: RDINSCOS Store






