Introduction
The FOLAI TH550 Stud Finder is a versatile wall scanner designed to accurately locate various hidden elements behind walls, floors, and ceilings. This device utilizes advanced sensor technology to detect metal pipes, live AC wires, wooden studs, steel bars, and supporting beams. It is an essential tool for professionals, homeowners, and DIY enthusiasts, ensuring safety and precision in construction and renovation tasks.

Image: The FOLAI TH550 Stud Finder device shown alongside a 9V battery, illustrating its compact design and power source.
Setup
- Battery Installation: The FOLAI TH550 requires a new 9-volt battery (not included). Open the battery compartment on the back of the device and insert the 9-volt battery, ensuring correct polarity. Close the compartment securely.
- Power On: Press the ON/OFF button to power on the device. The LCD display will illuminate.
- Initial Calibration: Before each use, or when switching modes, hold the device flat against the scanning surface (wall, floor, or ceiling) where you intend to scan. Press and hold the SCAN button (often integrated with the ON/OFF button or a separate side button) for 1-2 seconds until you hear a beep and the display indicates calibration is complete. This auto-calibration ensures maximum reliability and accuracy.

Image: A visual guide demonstrating the four key steps for using the stud finder: powering on and selecting a mode, calibrating, moving the device to scan, and marking the detected target.
Operating Modes
The FOLAI TH550 features five distinct scanning modes, each optimized for detecting specific materials and depths. Press the MODE button to cycle through the available options:
- Stud Scan (1/2 inch): Detects wooden beams and joists in drywall up to 0.5 inches (12 mm) deep.
- Stud Scan (1 inch): Detects wooden beams and joists in drywall up to 1 inch (25 mm) deep.
- Stud Scan (1.5 inches): Detects wooden beams and joists in drywall up to 1.5 inches (38 mm) deep.
- Metal Scan: Detects metal pipes, steel bars, and other metallic objects up to 2.36 inches (60 mm) deep.
- AC Scan: Detects live unshielded AC wires (85 to 240 volts) up to 2 inches (51 mm) deep.

Image: A clear visual representation of the five scanning modes: Stud Scan (0.5in, 1in, 1.5in), AC Scan (2in), and Metal Scan (2.36in), detailing their maximum detection depths.
The FOLAI TH550 is a multi-purpose tool designed for quick and accurate location of various hidden elements. It can identify stud edges, stud centers, wooden beams, metal pipes, rebars, and live AC wires, making it suitable for a wide range of detection needs.

Image: An infographic detailing the multi-purpose functionality of the stud finder, capable of quickly and accurately locating stud edges, stud centers, wooden beams, metal pipes, rebars, and live AC wires.
The device utilizes upgraded sensor technology for accurate detection of materials such as metal pipes, AC wires, wooden beams, and rebars, ensuring reliable results for various applications.

Image: An illustration highlighting the advanced sensor technology of the FOLAI TH550, showing its ability to detect metal pipes, AC wires, wooden beams, and rebars behind surfaces.
Operation Instructions
- Select Mode: After powering on and calibrating, press the MODE button to select the appropriate scanning mode for the material you wish to detect. The selected mode will be displayed on the LCD screen.
- Scanning: Place the device flat against the wall and slowly slide it horizontally across the surface. Maintain constant contact with the wall.
- Interpreting Display and Audio: As the device approaches a target, the LCD display will show signal strength indicators, and an audible beep will sound. The "CENTER" indicator will appear when the device is directly over the center of the detected object.
- Pinpointing: To pinpoint the exact center and edges of a stud or other object, move the device slowly back and forth over the detected area. Mark the points where the signal begins and ends to identify the edges, and the point where the "CENTER" indicator is strongest for the center.
- AC Wire Detection: The device continuously monitors for live AC wires in all modes. If a live AC wire is detected, a specific icon will appear on the display, and an alert will sound, helping to prevent accidental drilling into live electrical circuits.

Image: A visual explanation of how the stud finder identifies both the edge and the precise center of a stud, indicated by the LCD display and an accompanying audio alarm.

Image: This image demonstrates the device's capability to indicate live AC wires in all scanning modes, providing a crucial safety feature to prevent mishaps during drilling.
Maintenance
- Battery Replacement: When the low battery indicator appears on the LCD display, replace the 9-volt battery promptly to ensure accurate readings and optimal performance.
- Cleaning: Wipe the device with a soft, dry cloth. Do not use abrasive cleaners or solvents, as these can damage the casing or internal components.
- Storage: Store the stud finder in a cool, dry place, away from direct sunlight and extreme temperatures. If storing for extended periods, remove the battery to prevent leakage.
Troubleshooting
- Inaccurate Readings / Constant Beeping:
- Ensure proper calibration by holding the device flat against the wall and pressing the scan button for 1-2 seconds before moving it.
- Avoid placing the device directly over known objects during calibration.
- The device is highly sensitive; slight movements or uneven surfaces can affect readings. Try recalibrating and scanning slowly and steadily.
- Check for low battery. A weak battery can lead to inconsistent performance.
- No Detection:
- Verify that the correct scanning mode is selected for the material you are trying to detect.
- Ensure the device is in full contact with the scanning surface.
- Check the battery level.
- The depth of the object might exceed the maximum detection depth of the selected mode.
- LCD Display Not Working:
- Check the battery. Replace if necessary.
- Ensure the device is powered on.
Specifications
| Brand | FOLAI |
| Model Number | 550B (TH550) |
| Item Weight | 9.2 ounces |
| Package Dimensions | 8.31 x 3.27 x 1.54 inches |
| Power Source | Battery Powered (9V battery required) |
| Voltage | 240 Volts (AC detection) |
| Included Components | Stud finder (battery not included) |
| Stud Scan Depth | Up to 1.5 inches (38 mm) |
| Metal Scan Depth | Up to 2.36 inches (60 mm) |
| AC Scan Depth | Up to 2 inches (51 mm) |
Warranty and Support
Information regarding product warranty and customer support is not available in the provided product data. Please refer to the product packaging or the manufacturer's official website for details on warranty coverage and how to contact customer support.