Moisture Meter Pen FLIR MR40

The FLIR MR40 is a pocket-sized, rugged moisture meter pen for quick measurement of moisture content in wood and other building materials. It combines a simple LCD display, integrated replaceable pins, and an integrated flashlight to provide reliable moisture checks for builders, inspectors, technicians, pest-control specialists, roofers and flooring contractors. The device uses electrical resistance to report moisture content in a 5%–60% range and includes a hold function and a pin calibration check located in the cap.

Advantages

The MR40 is compact and lightweight, designed for portability and field use with splash-proof IP54 protection and drop resistance from 3 meters. It offers clear, fast readouts on an LCD, audible range signaling, a battery condition indicator and long battery life. The unit ships with replaceable pins (four included) and provides a simple calibration/pin-check feature for reliable measurements.

Suitable for

• Quick moisture checks in timber and building materials
• On-site inspections by builders and inspectors
• Restoration and water-damage assessment
• Pest-control moisture surveys
• Roofing and flooring contractors performing site checks

Key specifications

• Measurement principle: electrical resistance
• Measuring range: 5% to 60% moisture content (MC)
• Measurement accuracy: 5–30% MC: ±2%; 30–60% MC: informational only
• Electrode pins: integrated, replaceable (4 pins included)
• Display: LCD with hold function
• Flashlight output: approximately 40 lumens
• Automatic switch-off: 3 minutes
• Operating temperature: -10 °C to 60 °C
• Dimensions (H×W×L): 193 × 26 × 31 mm
• Weight: 80 g (with batteries)
• Battery type and life: 2 × AAA alkaline, up to 70 hours (without flashlight)
• Protection rating: splash-proof IP54

How to use

Insert two AAA alkaline batteries and press the on/off button to power the MR40; the unit will automatically switch off after three minutes of inactivity. Place the integrated pins into the material to be tested and read the moisture value on the LCD; use the hold function to lock the displayed reading if needed. Refer to the pin-check feature in the cap to verify calibration before measurements and replace pins when worn.

Usage recommendations

For accurate interpretation, use the MR40 primarily on standard building materials; for plywood, drywall and oriented strand board (OSB), consult the MR40 material conversion table. Avoid relying on readings above 30% MC for precise quantification, and keep the pins clean and undamaged for consistent results.