Tramex MRHIII Slide Hammer

Our Score:

Tramex MRH III at a glance

The Tramex MRH III, a digital hand-held electronic impedance moisture meter, offers a hammer probe accessory for taking measurements deep within the wood. This is one of three modes of operation incorporated into this meter.

It is capable of measuring moisture in wood and a variety of other materials including masonry, drywall, and laminate. Among the key features of this meter is a specific gravity adjustment for most wood species, a backlit, easy-to-read LCD display, and a HOLD function that enables users to “freeze” the reading.

This hammer probe accessory is worth buying based on its overall accuracy and versatility.


  • Scored high in accuracy.
  • Versatile: 3 modes of operation and able to be used with a variety of building materials.
  • Built-in specific gravity adjustment for most wood species.
  • Useful features: HOLD function that enables users to “freeze” the reading, and a backlit LCD display.


  • Adjustments for temperature require using a table.
  • Problems with fluctuating readings.
  • Surface moisture interferes with moisture readings.
General MM70D Moisture Meter Review

Tramex MRH-III Moisture Meter

Before buying the Tramex MRH III moisture meter learn how it did in our testing.

Objective Evaluation – Overall Score 4.1 out of 5.0

Tramex MRH III Slide objective

Accuracy – 4.3 out of 5.0

This meter’s hammer probe provided reasonably accurate moisture content readings in the low to medium MC range when compared to ASTM D-4442 oven dry measurements. In the very low MC range, however, it could only read 0% due to its inability to read below 5% MC. Also, there was a decrease in accuracy above 22% MC.


Learn about our accuracy test procedures

Surface Moisture – 1.0 out of 5.0

The surface moisture test showed a difference of 7.3% in MC readings from the baseline. Results indicate that operating this meter in high humidity environments where condensation may form on the surface could lead to questionable readings.


Learn about our surface moisture test procedures

Meter Temperature – 4.7 out of 5.0

Meter temperature had some effect on this meter’s readings.

A low meter temperature of 34.8° F in the presence of low MC increased the reading nearly 2% compared to the room temperature reading. In the presence of high MC, the reading showed no change.

A high meter temperature of 110° F in the presence of low MC showed only a 0.2% increase in the reading. In the presence of high MC, the reading showed a difference of 1.1%.


Learn about our meter temperature test procedures

Wood Temperature – 4.0 out of 5.0

Wood temperature had a small effect on this meter’s readings.

Readings taken with a low wood temperature of 33.6° F in the presence of low MC had a small increase of 0.8%, and high MC showed a decrease of 0.5% from the room temperature reading.

Readings taken with a high wood temperature of 110° F decreased 1% in the presence of low MC when compared to the room temperature reading. In the presence of high MC, the reading decreased 2.7%.


Learn about our wood temperature test procedures

Reading Repeatability – 3.0 out of 5.0

This meter did not give consistent, repeatable readings. One of the few meters we tested that did not provide a high level of repeatability.


Learn about our repeatability testing procedures

Drift – 3.0 out of 5.0

The Tramex MRH III hammer probe readings did not hold steady. They continually fluctuated, requiring the user to record readings very quickly.

Tramex MRH III Hammer drift

Cable Interference – 5.0 out of 5.0

Cable interference caused only a very small change in this meter’s MC readings.


Learn about our cable interference and drift testing procedures

Subjective Evaluation – Overall Score 3.2 out of 5.0

Tramex MRH III Hammer subjective

Learn about our subjective testing procedures

Ease of Use – 2.8 out of 5.0

This meter is simple to operate with little use of the manual needed to get started. Documentation in the manual is clear and easy to understand. Battery installation requires the use of a screwdriver or other tool.

Quality – 4.3 out of 5.0

Manufactured in Ireland. This meter has a solid and durable feel and appears unlikely to malfunction or break with normal use. Insulation on the hammer probe pins isn’t complete, so the blue insulation came off after the first couple of readings.

Comfort – 3.0 out of 5.0

Larger and bulkier than most meters we tested. Does not readily fit into a pocket but when used with the supplied soft case, it can be attached to a belt for easy transport. Large, high-quality buttons for easily adjusting the settings.

Versatility – 4.0 out of 5.0

This meter incorporates three modes of operation—pinless, hammer pin probe, and hygrometer. Can be used on wood as well as drywall, wood plaster, brick, ceramic, and most other building materials. Features a built-in specific gravity adjustment for most wood species.

Note: We only performed our accuracy tests for this meter on various species of wood, and did not assess its accuracy when used with other non-wood materials.

Range – 2.3 out of 5.0

The meter is capable of measuring moisture content across a range from 5% to 30%, but it will only read down to 7% when using the hammer probe.

Features – 3.5 out of 5.0

Readings precise to the nearest 0.1%. Low battery indicator. Also features a HOLD function, a backlit LCD display for poorly lit areas, and an audible alarm. Can measure moisture content over 1 inch deep into samples, depending on the material and meter setting.

Customer Service – 4.0 out of 5.0

Customer service is friendly and knowledgeable. Prompt email response but telephone response time slower than many other manufacturers. Manual available online.

Warranty, repairs, and calibration:

  • Warranty covers 1-year parts & labor. However, damage due to dropping the meter is not covered.
  • Repair costs are not quoted over the phone, but a free estimate is provided when the meter is sent to Tramex.
  • Turnaround time on repairs is 7 days plus time for shipping.
  • Customer pays to ship both ways.
  • Tramex sells a device to check the calibration, but it doesn’t calibrate and is not NIST certified.
  • Repairs carry a 90-day warranty for parts and labor.
  • Recalibration is not covered under this warranty.

Our review is based on Moisture Meter Experts independent evaluation of the meter, which was purchased by Moisture Meter Experts or provided free of charge by the manufacturer. By purchasing this meter through the links above, Moisture Meter Experts may be compensated either by your purchase directly from Moisture Meter Experts or from commissions from an affiliate. View our Review Procedures section to learn more about our proprietary evaluation procedure and expertise in the field of moisture meters.