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Handheld moisture meter MMD900 with dual pins on top, pinless sensor on back, rubber side grips

General Tools & Instruments

General Tools & Instruments MMD900 moisture meter

SKU CH-4ZQ4-6JHSB

Detects moisture in wood, drywall and concrete up to two inches deep with pin and pinless modes plus a 40-dot LED bar graph

  • TypeMoisture Meter
  • Pin and pinless modes cover surface and deep moisture detection
  • 40-dot tri-color LED bar graph plus jumbo LCD show readings at a glance
  • Detects leaks up to 2 inches behind walls and ceramic tile
  • Auto power-off after 3, 5, or 10 minutes extends battery life
  • Includes remote pin probe on 46" cable and protective cover that doubles as calibration checker

Dual-mode moisture meter

The General Tools MMD900 combines pin and pinless sensing in one handheld instrument. It measures wood moisture content directly or scans relative dampness behind surfaces without penetration. A remote probe on a 46 inch cable extends reach into cavities and tight spots. The tool is aimed at contractors, woodworkers and homeowners who need to verify building materials are dry.

Suited for mixed-material inspection

Users who must switch between destructive pin readings on lumber and non-invasive scans of drywall, concrete or tile will benefit from the two modes. The tri-colour LED bar graph and audible alarm give instant wet-zone feedback. Buyers who only need a basic pin meter for firewood or a dedicated deep-scanning device for thick concrete slabs should consider simpler or more specialised alternatives.

Reads surface and subsurface dampness

Pin mode displays percentage wood moisture equivalent while pinless mode detects moisture up to 2 inches behind walls and ceramic tile. The 40 segment LED bar graph shows low, medium and high levels at a glance. Auto-zero calibration and a hold function lock readings for recording. Auto power-off after 3, 5 or 10 minutes preserves the 9 V battery during extended job-site use.

Highlights

  • Pin and pinless modes cover surface and deep moisture detection
  • 40-dot tri-color LED bar graph plus jumbo LCD show readings at a glance
  • Detects leaks up to 2 inches behind walls and ceramic tile
  • Auto power-off after 3, 5, or 10 minutes extends battery life
  • Includes remote pin probe on 46" cable and protective cover that doubles as calibration checker

Specifications

TypeMoisture Meter

Questions about this item

What power source does the MMD900 moisture meter require to operate?

The meter runs on a 9V battery, which is included with the device.

Can the pinless sensor on the MMD900 detect moisture through ceramic tile?

Yes, the pinless sensor on the back can detect water leaks up to 2 inches behind walls and ceramic tile.

How can I verify the MMD900 is calibrated correctly after setup?

The protective cover doubles as a calibration checker; use it to confirm the meter reads accurately before testing materials.

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