Extech MO257 Pinless Moisture Meter
The Extech MO257 is a non-invasive “pinless” moisture meter that measures moisture content in wood and building materials without piercing the surface. It provides numerical readings from 0.0 to 100.0 (with 0.1 resolution), supports depth sensing to about 0.78″ to 1.6″ (20 to 40 mm), and includes features like a backlit triple-LCD display, adjustable high/low alarms, and automatic calibration—making it ideal for restoration, inspection, and quality-control tasks.
Description
The MO257 meter employs high-frequency sensing technology to detect moisture within materials beneath the surface, eliminating the need for pins or probes that could damage finishes or require invasive testing. Upon power-up, the unit can auto-calibrate in “dry air” and then provide relative moisture readings tailored for wood and building substrates. The large triple-segment backlit LCD shows the current moisture percentage, plus stored maximum and minimum values, and indicators for hold, alarms, and battery state. Two user-programmable alarm thresholds can be set—one for a “RISK” level and another for a “WET” level; when the readings exceed those levels, the meter triggers audible beeps and visual flashing alerts. The meter’s range (0.0–100.0) and fine 0.1 resolution allow detailed tracking of moisture trends. With a measurement depth reaching approximately 20 to 40 mm, the MO257 is capable of assessing moisture not only at the surface but into the substrate, which is crucial for materials like laminated floors, drywall, or tiled surfaces. Additional convenience features include a Data Hold function, a low battery indicator, and an auto power-off mode to preserve battery life. It’s powered by three AAA batteries and comes with a carrying pouch for site use. Rugged and ergonomic, this tool suits professionals needing reliable, damage-free moisture assessment in building materials.
Features
- Non-destructive, pinless measurement – No pins inserted into materials means less surface damage and faster testing.
- Deep sensing capability (~20–40 mm) – Allows detection of subsurface moisture issues in layered materials.
- Wide numerical range with fine resolution – 0.0 to 100.0 scale with 0.1 increments enables accurate moisture readings.
- Backlit triple-LCD display – Shows the moisture value, MAX/MIN readings, and status icons for alarms, hold, and battery.
- Dual alarm thresholds with visual/audible alerts – Two user-set levels (RISK and WET) trigger warnings when exceeded.
- Automatic calibration on startup – Simplifies use in varying environments by calibrating in dry air.
- Data Hold, MAX/MIN memory – Freeze readings and review extremes during a measurement session.
- Low battery indicator and auto power-off – Enhances field usability and battery life.
- Broad material compatibility – Suitable for wood, drywall, plaster, tile, and other building materials.
- Portable design with included pouch – Lightweight and easy to carry for on-site inspections.
Includes
- 3x AA Batteries
- Pouch Case
