Mag Pro II—Magnetic Gradiometer or Precision Magnetic Locator

The Dunham & Morrow Mag Pro II magnetic gradiometer is designed for use by geologists, surveyors, hydrologists, archeologists, criminologists, and any other professional with a need to survey an unknown target field. It can precisely pinpoint any ferrous target including knives, guns, survey markers, iron or steel pipes, water valves, water meters, or any other ferrous object covered by dirt, pavement, water, snow or ice.

The world’s most sensitive magnetic gradiometer
• 4 ranges: 2,000, 200, 20 & 2.0 milligauss
• Made in the USA
• Lifetime Warranty
• Satisfaction guaranteed or your money back

Now you can find smaller targets at a much greater depth.

The instrument of choice for any serious magnetic search is the Dunham & Morrow Mag Pro II. First introduced in August of 2010, this latest update of the Mag Pro II design increases the instrument sensitivity by a factor of ten. The Mag Pro II can now be used to locate smaller and deeper ferrous targets, targets that were previously undetectable.

With the Mag Pro II, you can survey a field, a meadow or a shallow-water bog in a matter of minutes and precisely locate any ferrous target such as a knife, a gun, a survey marker, a buried storage tank, or a 55-gallon drum, to name a few. Shock-mounted sensors maintain proper sensor alignment even when exposed to harsh physical abuse. The sensors are waterproof from the bottom of the electronics housing to the sensor tip so you can even perform magnetic surveys of shallow lakes and rivers. We suggest that you perform a general survey of the area of interest on the 20 milligauss range and then increase the instrument sensitivity as needed for a more comprehensive magnetic survey of the same area.

Made in the USA, and the only user-friendly, precision single-axis magnetic field gradiometer on the market, the Mag Pro II’s top-mounted LCD panel meter displays the magnitude of the magnetic field in milligauss. In addition, the instrument produces an output that is directly proportional to the magnitude of the external magnetic field gradient.

The new Mag Pro II now has a fourth range. In addition to the 2,000, the 200 and the 20 milligauss ranges, we have now added a 2.0 milligauss range.

The Mag Pro II typically provides an impressive 40+ hours of operation from a set of standard alkaline batteries. The Low-Battery indicator LED flashes when you have between 2 and 3 hours of normal operating time left.

The Mag Pro II is unique in its ability to measure the DC magnetic field gradient of any ferrous target but it also has another unique ability; the ability to measure low frequency, AC magnetic fields.

General Specifications
Display meter:
3½ digit, LCD (0 to ± 1,999)
Ranges (Full Scale):
• 2000 milligauss
• 200 milligauss
• 20 milligauss
• 2 milligauss

Audio Output
Variable frequency audio output proportional to the differential magnetic field

Overall accuracy:
± 1 % of FS

Low Battery Indicator
RED flashing LED

Temperature Range
(32 – 90) °F, (0 – 33) °C

2.0 lbs. (0.9 kg)

42 ½” x 3 ¾” x 1 ¾, (108 cm x 9.5 cm x 4.4 cm)

36” (91.4 cm) base of electronics to tip of sensor
Operating time
40 hrs, 4-AA alkaline batteries


Lifetime Warranty – Mag Pro II Magnetic Gradiometers are warranted by Dunham & Morrow to be free from defects in material and workmanship. This warranty is extended to the owner of the product and is valid for the lifetime of the product; a period that extends no less than 25 years from the date of purchase. The batteries and meter are specifically excluded from this warranty as is exposure of the internal electronics to salt water or battery acid corrosion.
Archeological uses for the Mag Pro II:
For years Archeologists have been using precision magnetic gradiometers like the Mag Pro II, to survey historical sites. By performing magnetic surveys of a historical area you can usually identify the location of old walls, fire pits and trash dumps. All of these produce low level surface magnetic anomalies that offer an insight into the area’s past usage, and they are relatively easy to locate. The heat of the fire leaves its mark on the magnetic field of the surrounding material. Decaying walls can be outlined from the small iron targets that were once part of the wall or wall surface that after the wall decayed are now imbedded in the soil directly beneath. Similarly, the village trash dump frequently has a mixture of discarded magnetic material that remains and helps pinpoint the dump location.

“This is the shell I found with your locator. It is a seven inch Harding and weighs fifty pounds. It was made in Charleston during the civil war and only used in this area…..Gary”
–The last time I checked with Gary, he had found three more shells all smaller.

Meteorite Detection:
Meteorites can be divided into three categories: Chondrites, Achondrites and Iron meteorites. The Iron meteorites make-up only 6% of all meteorites, however they are readily detectable by the Mag Pro II and they can be quite valuable. So grab your Mag Pro II and go searching. Have some fun and maybe make a few dollars while you are at it. Meteorites can be found all over the world. Central Canada and the high plateaus of our Western States are prime search areas because the meteorites impact the Earth before being entirely consumed while entering the Earth’s atmosphere. Africa and Antarctica are also prime areas to search. Creek beds are also an area of interest, just watch your step and don’t submerge the electronics.

Hydrologist and Oil Companies:
The Mag Pro II has unequalled sensitivity for detection of deep old water wells as well as abandoned or “Capped” oil wells can be located using the Mag Pro II. Old Wells that are now recognized as potentially valuable resources could be mapped and recorded for possible future resurrection. 

It may not be the most glamorous task, but since the Mag Pro II can be used to easily pinpoint discarded guns or knives, it can also be used to pinpoint illegally buried waste material.
Finding Buried Treasure
One potential target that should not be overlooked is a magnetic field anomaly also referred to as a "magnetic hole". Magnetic holes are just that, a discontinuity in the magnetic field created by man simply digging a hole. At any specific location on the Earth’s crust, you can usually detect an overall background magnetic field. At first you may think that this is an instrument calibration problem and your thought is to have the instrument recalibrated. However, if you allow for the possibility that your local search area can have an overall magnetic field offset, then the world opens up for you. When man digs a hole, he randomly distributes the magnetic particles that are part of the soil. This is done shovelful by shovelful. These small magnetic field variations are one way that archeologists are able to locate old water wells, caves, root cellars, tomb entrances and in some cases, lost treasure troves. To keep his valuables safe, man has been burying his treasures for millenniums.

The treasure trove pictured here was discovered by
Ayub Basha in India. It was buried at a depth of 3 meters and he located it using a Dunham & Morrow magnetic locator. Fortunately for him, he had ready access to a back hoe.

For more information please visit