Bosch Professional Stud Finder Gms 120 (Drill Hole Marker, Max. Detection Depth Wood/Magnetic Metal/Non-Magnetic Metal/Live Cable: 38/120/80/50 Mm, In Cardboard Box) – Amazon Exclusive Se

Bosch, GMS 120
  1. Bosch, GMS 120

    Metal Setting

    The standard detection setting, the metal setting provides the best detection for magnetic (≤12cm) and non-magnetic (≤8cm) metals and can detect live wires up to a depth of 5cm on various wall types.

  2. Bosch, GMS 120

    Live Wire Setting

    While all settings detect live wires, the Live Wire setting provides best results when detecting live wires is the focus and can accurately detect them up to a depth of 5cm on various wall types.

  3. Bosch, GMS 120

    Drywall Setting

    Specialized for use with drywall, and can detect wooden and metal studs ≤ 3.8cm deep and live wires up to a depth of 5cm. This settings should only be used if the detection of wooden studs is needed.

Bosch, GMS 120
  1. Bosch, GMS 120

    Apply Voltage

    Make sure voltage is applied to the cable being searched for (i.e. by turning on the light)

  2. Bosch, GMS 120

    Remove Interferences

    Remove jewelry and gloves. Turn off nearby electronic devices that could interfere with detection

  3. Bosch, GMS 120

    Choose a Setting

    Turn on the device and select the correct detection setting for the application

  4. Bosch, GMS 120

    Start Detection

    Hold the tool by the rubber grip. Place the tool flat against the wall. Move 3x in each direction

  5. Bosch, GMS 120

    Record Results

    Transfer detection results to the wall by using the marking hole

1 Apply Voltage 2 Remove Interferences 3 Choose a Setting 4 Start Detection 5 Record Results

Product Comparison

Bosch, GMS 120

GMS 120

Bosch, D-tect 120

D-tect 120

Bosch, D-tect 150

D-tect 150 SV

Bosch, D-tect 150 SV

D-tect 200 C

Max. detection depth
120mm 120mm 150mm 200mm
Live wires
Non-live cables
Plastic Pipes
Material classification
Live-wire/Metal Live-wire Live-wire/Metal Live-wire/Metal
Bosch Radar Technology
Spot measurement
Depth indication
Display max. drilling depth
Display object depth

Why does the signal change when I move along a live wire?

Twisting of leads of live wires causes variation in the strength of an electric field on the surface up to complete extinction. In case of a 3-phase live wire, the different phases of live leads cancel each other out.

Why do I have problems detecting a wooden stud in drywall?

Make sure to measure on homogenous drywall (e.g. no hidden holes or OSB walls). Choose the drywall setting before positioning the device on the wall, then wait until the LED ring turns on and start moving the device 3x over the area of interest.

Why does the device indicate live wires everywhere?

The device detects live wires by capturing the signal emitted by the live wire. If a wall has a high conductivity, this signal can be spread and over whole wall. Or, if a live wire runs parallel to rebar, all rebar might be shown as live wires.

What should I do if the device displays different results for the same measurement?

Follow the step-by-step guide when using the tool and make sure to do all the measurements the same way. In particular, move the tool 3x in each direction and keep the outer conditions constant.

Why does the device indicate metal objects on the whole wall?

The tool detects aluminium foil on underfloor heating systems and on thermal glass wool insulation as metal, and likewise detects brick reinforced w/steel fibre as metal due to the high iron content. It may show a yellow light w/red bricks or tiles.

Weight: 270 g
Dimensions: 25.8 x 16.7 x 7.3 cm; 270 Grams
Model: GMS 120
Part: 0601081005
Colour: Blue
Pack Quantity: 1
Batteries Required: Yes
Batteries Included: Alkaline
Manufacture: Bosch Professional
Colour: Blue
Quantity: 1

65 Responses

  1. Anonymous says:

     United Kingdom 🇬🇧

    The whole package is good ie nice case and marker . The stud finder is OK only used a couple of times though so time will tell

  2. Gilberto37C says:

     United Kingdom 🇬🇧

    Great product and from Amazon warehouse
    Bargain and I’m much safer with my DIY

  3. RandellBoismenu says:

     United Kingdom 🇬🇧

    Got this for my bf for Christmas he said it’s good

  4. RolandoMcneely says:

     United Kingdom 🇬🇧

    Golden Review Award: 2 From Our UsersGenerally I dislike reading instructions but for this piece of equipment you do have to follow the advice for accurate results.
    Get used to it by testing on surfaces where you know what it should find. Take it slowly and once you become used to the way it works you’ll have confidence that your work is safe or not.

  5. Anonymous says:

     United Kingdom 🇬🇧

    Bought as a present for my brother, who does use it and is very happy with it. It works and that all that matters.

  6. Anonymous says:

     United Kingdom 🇬🇧

    It comes with its own carry case very well made produc

  7. HaleyCuningham says:

     United Kingdom 🇬🇧

    Golden Review Award: 35 From Our UsersThis is a review of the Bosch GMS 120 stud scanner.

    I bought this device despite all the negative reviews as I know Bosch make quality stuff and in any event if it’s really an awful piece of kit, Amazon will let you return it for a full refund.

    In the first few minutes of using this device I found all the problems people had been complaining about, so I decide to read the instructions. Once I had done so and followed other guidelines I found on-line, I found it worked perfectly. The cure for some issues are not obvious — like removing your watch and any rings together with any external interference from mobile phones, tablet computers and any metal objects in the vicinity that don’t need to be there. The device is very sensitive and using two hands instead of one to move the scanner can lead to false readings.

    I found the indications from the device to be very informative for example if it finds a metal source whether that be a nail, screw or metal stud attaching the plasterboard to the stud it will tell you if its magnetic or not, which may give you an idea of the source. It will also detect plastic pipes containing water when scanning in the bathroom so you need to be alert as to what you are looking for. In my case I was looking for wooden studs so that I could install a particularly heavy bathroom cabinet. It easily found the studs despite scanning through quite thick porcelain tiles on top of the plasterboard.

    All in all I found the device to be very useful and great value for money.

  8. GerardoZLP says:

     United Kingdom 🇬🇧

    Golden Review Award: 2 From Our UsersWhat I liked was it’s ability to find and detect, electrical wiring, metal, and wooden and metal beams inside of dry walls. What I Also liked the marker pen for marking areas of detected items when you use the ,measuring indicator, and the fine scale indicator that will help you to mark the exact spot of the item detected. Read the instruction manual to get the full potential out of the unit and read about maintenance and about putting the tool away after use and how to over come faults or calibration faults. Overall it’s a very well made tool that just shows quality. And for your own safety it’s a must have tool, because you don’t know what’s inside the wall your thinking of drilling into too place a item or construction or DIY. Dislike none yet.

  9. ValerieCoons says:

     United Kingdom 🇬🇧

    Initially, I thought what a pile of junk, it seemed wildly inaccurate on electrical cables, but after watching a few videos on you tube, and reading the manual, yes reading the manual. I could identify cables, beams and what ever I needed correctly.
    When I first started to use it, lots of false readings, but now I know its limitations, mainly user error. I like it much more. once you realize how to stop false readings, it’s accuracy is quite good.

    This appears to be a easy bit of kit to use, but don’t be fooled. It take time to learn, requires reading the manual, and watching a few YouTube videos, to educate yourself on how to get the best from it. Mine is good now.

  10. Anonymous says:

     United Kingdom

    I read a lot of reviews before buying and I’m glad I didn’t focus on the negative ones too much. This is a great tool to give safe and accurate information. I’m not a regular DIY-ER but this was easy yo use and well worth the price for the reassurance that I wasn’t drilling into cables etc.

  11. Dante7596hpk says:

     United Kingdom

    Be sure to read the manual and take a bit of time to learn how to use it properly, or frustration and annoyance will fall upon you!
    The device itself is well made and very capable, with good haptics and features. It’s perhaps a bit on the expensive side but otherwise no complaints.

  12. IslaEastwood says:

     United Kingdom

    It may just be me, but I have not found this product to be as reliable as I would wish. Perhaps it just takes a lot of practice, but I would expect a relatively expensive meter such as this one to locate known studs and wiring quickly and reliably. It doesn’t. Sometimes it pinpoints the centre of a stud or joist very accurately, other times it misses the same target completely. I find that I need to combine the readings from the meter with another more low tech way of checking the location of studs (ie drilling little holes) before I commit to identifying the outline of the stud. Consequently it is of limited use to me.

  13. Anonymous says:

     United Kingdom

    Wanted to put some holes in a wall that had pipes/cables, and wanted to be sure i didn’t cause myself some large bills for tradesman to fix my mistakes.

    Read some reviews and picked this device, and glad i did.

    I’ve used this to find cables and pipes in walls, and concrete floors, and its worked brilliantly, and (touch wood) i havnt caused myself any expensive bills since,

    80 sounds expensive, but is far cheaper than fixing any issues this prevents.

  14. Anonymous says:

     United Kingdom

    I have used Cheaper scanners in the past that seem to beep all the time and I could never be sure where to drill. I used this scanner over known wires/pipe areas on my interor (plasterboard) walls and I always got the results expected so I have confidence in this scaner

    I watched a few YouTube videos before hand on usage and always make sure my phone is no where near it.

    So far for me a great bit of ki

  15. Anonymous says:

     United Kingdom

    Great tooldoes exactly what it says it will do and with a good degree of accuracy too found it great for locating items buried in walls, and this saved my neighbour from going through a load of cables running everywhere in the walls of his kitchen well worth having this in your tool box I’ve had a few locators over the years, but this is the best I’ve ownedwell pleased with i