Model # GMS120

Internet #202850662

Bosch Digital Wall Scanner with Modes for Wood, Metal, and AC Wiring


Digital Wall Scanner with Modes for Wood, Metal, and AC Wiring

  • Lightweight design
  • Durable and dependable
  • Suitable for a wide range of projects
$79.00 /each

Frequently Bought Together

Product Overview

The New Bosch GMS120 Wall Scanner features Multi-Mode Detection-For wood studs, metal objects (rebar, studs and steel/copper pipes) and live wiring. Illuminated Graphical LCD Display-Indicates mode, detection strength and more. Deep Metal Detection Capability-Detects steel up to 4-3/4 in. (120 mm) deep in cured concrete. Automatic Center Finder-For locating center of detected wood or metal object. 3 Selection Modes (Wood, Metal, AC Wiring) with automatic calibration for easy and precise detection. Audible Detection Signal-With On/Off button. Ergonomic Soft-Grip-For secure grip and comfort. Illuminated ring indicates detection status.

  • Max detection depth copper wiring: up to 2 in.
  • Max detection depth ferrous metals (steel): up to 4-3/4 in.
  • Max detection depth nonferrous metals (copper): up to 3-1/8 in./80 mm
  • Max detection depth wood substructures (studs): up to 1-1/2 in.
  • Operating temperature: 14°F/-10°C-122°F/50°C
  • Great solution for all your detection needs


  • Click here for more information on Electronic Recycling Programs

Info & Guides

You will need Adobe® Acrobat® Reader to view PDF documents.  Download a free copy from the Adobe Web site.




Warranty / Certifications

More Products With These Features


Customer Questions & Answers

is the battery included?

Asked by: Anonymous
Yes, a 9V battery is included. The answer from Bosch on your question is actually wrong.
Answered by: Doresoom
Date published: 2017-02-01

what is the availabliy of the gms120 Bosch wall scanner--in store???--thank you

Asked by: Anonymous
They do have them in stock when i bought mine. It is a good by. I have tried other stud sensors and this one beats them hands down.
Answered by: hobbistlan
Date published: 2015-11-08

Can it detect water leaks Can it detect over cement

Asked by: Alexis
Thanks for your question. The GMS120 is designed for detection of wood studs, metal objects (rebar, studs and steel/cooper pipes) or live wiring. We do not make a product that will detect water leaks.
Answered by: BoschTools
Date published: 2016-06-24

what types of wire will it detect.

Will it detect live and non-live (disconnected) electrical wire?
Asked by: Bahr
It did not detect any live wires when my other, much cheaper, stud detector did. It won't detect electricity even when I put it over a switch that's on!
Answered by: AG
Date published: 2017-03-11
  • y_2017, m_3, d_21, h_24CST
  • bvseo_bulk, prod_bvqa, vn_bulk_1.0.0
  • cp_1, bvpage1
  • co_hasquestionsanswers, tq_10
  • loc_, sid_202850662, prod, sort_[SortEntry(order=NUM_ANSWERS, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING), SortEntry(order=LAST_APPROVED_ANSWER_SUBMISSION_TIME, direction=DESCENDING), SortEntry(order=LAST_APPROVED_ANSWER_SUBMISSION_TIME, direction=DESCENDING), SortEntry(order=BEST_ANSWER_FEEDBACK_COUNT, direction=DESCENDING), SortEntry(order=POSITIVE_ANSWER_FEEDBACK_COUNT, direction=DESCENDING), SortEntry(order=NUM_ANSWERS, direction=DESCENDING)]
  • clientName_homedepot
  • bvseo_sdk, java_sdk, bvseo-3.1.1
  • CLOUD, getContent, 18ms

Customer Reviews

Digital Wall Scanner with Modes for Wood, Metal, and AC Wiring is rated 3.5 out of 5 by 57.
Rated 5 out of 5 by from Great ... Great
Date published: 2017-01-17
Rated 1 out of 5 by from I bought this to help with professional and personal projects. When we do handrails in the houses... I bought this to help with professional and personal projects. When we do handrails in the houses we build sometimes the blocking installed during framing isn't exactly where it's supposed to be, so having a good wall scanner is important, especially since just finding the studs isn't sufficient if we want the handrail brackets to be properly spaced. So I got the GMS120 and started trying it on some remodel work, where I had a 5/8" drywalled wall that was open on one side and had pipes and live wires in the cavity. I compared the GMS120 to my Zircon that cost waaaay less. Zircon: Found every stud, and alerted at the wire. No false positives. Some of that annoying erroring out, but otherwise good. Bosch: Found lots of non-existent studs. Sometimes alerted at the correct studs, but not always. Gave a lot of alerts about metal where there was no metal, flipping between ferrous and non-ferrous. DID NOT ALERT AT LIVE WIRES. Gave alerts for wires nowhere in the vicinity of live wires. What's more, the Bosch GMS120 is IMPOSSIBLE to view if it is below eye level at all. The LCD display has been oriented or polarized in a way that means you have to be 90 degrees or less below perpendicular to the plane of the LCD. This means most of the time you need to use the GMS120 upside down or sideways, unless you want to always be crouching. This is made worse by the all the false alerts the GMS 120 gives, so you really need to watch the screen to see if it's alerting to metal or a non-existent wire or alerting to a stud. The manual is atrocious. It is entirely unclear how to calibrate the unit once it's placed on the wall (press the wood/metal/elec mode button), and there's no *clear* description of how to use the scanner. There's a lot of flipping back and forth in the manual between general use instructions and specific mode usage. The interjection of part/button numbers in the text is odd and distracting. I am returning this.
Date published: 2017-03-11
Rated 4 out of 5 by from Quality Wall Scanner I was frustrated buying cheap, throw-away stud finders that never seem to work when you need one, so I stepped up to the Bosch GMS120 Professional Wall Scanner. It comes with a nice flexible storage case with hand lanyard and belt loop. Using this wall scanner is not intuitive and requires reading the instructions thoroughly. There are multi-colored flashing lights, changing bar graphs, symbols and sounds that requires prior working knowledge to use properly. The instruction pamphlet would benefit from better graphics and illustrations. The scanner has three modes; wood, metal or live electrical. In the wood mode it actually scans for all three, and will display the various signals and graphs on the display. It also identifies the center point of wood studs or metal objects. Selecting metal mode excludes wood and scans for only ferrous/non ferrous metals and “live” electrical wires. It is important to note that the scanner detects wires where current is flowing. The warning light may not flash for wires that have no current draw. The Bosch GMS120 performed very well in all three modes during my testing and use. As recommended in the instructions, I used a thin piece of cardboard over the uneven ceiling texture, and it detected the joists perfectly. Now I don’t have to drill and patch holes in the ceiling when looking for the joists. The scanner could be more user friendly with better graphics in the display, but it’s still a giant leap above the cheap stud finders.
Date published: 2013-04-25
Rated 2 out of 5 by from Disappointing This stud finder really sounds like it does it all: find studs, live wires, and metal in the wall. However, I was very disappointed that it didn't perform better for the price. My $15 stud finder outperformed it on several of the walls that I tested it out on, which is inexcusable in my book. Initial impressions: - The stud finder is a little bit larger than most I've used in the past. - Bosch packed a lot of features into this, including a 3-color led indicator, a signal strength display, a backlit display, the option to turn sound indications on/off, and the option to turn the backlight on/off. - The through-hole for marking stud locations is a pretty cool feature too. Wood stud detection: - The main application I planned on using this for was locating studs. I started over an electrical outlet, since I knew there should be a stud on one side of it. I used both stud finders (my old one and this one) simultaneously, and my old one lit up reliably every 16", turning on and off for each side of the stud. The Bosch gave me intermittent indications, some of which were right in the middle of the 16" spans. The centering feature is OK, but requires that you backtrack once you reach the far side of the stud. Even then, it usually gives about a 3/4" range that it calls the "center." Metal detection: - The best-performing feature is the metal detecting capability. This is the only reason I'm giving it more than one star. I do a bit of woodworking, and missing a nail before I send a board through my planer can cost me $50-60 on a set of knives. So if I find two nails, the scanner has paid for itself. I tried it out by holding a screw on the far side of an 8/4 walnut board, and the scanner gave a strong indication when I passed over the screw's location. It couldn't find a staple through the board though, but it can detect a sewing needle from about 1/4" to 1/2" from the scanner, without anything in between. - If you want a more reliable stud finding method, I'd use the wood detection capability in conjunction with the metal detection feature. Find the general location of the stud with the wood detection, then use the metal detector to scan up and down to find the screws. Live wire detection: - This thing is garbage when it comes to finding live wires in your walls. I can scan all around electrical outlets and light switches without so much as a peep from it. My old $15 stud finder lights up like crazy when I scan the same areas. I even scanned the extension cord powering an overhead light in my garage, and the Bosch scanner couldn't pick it up even when I touched them together! I had to rub the wire all over the scanner until it lit up. I would definitely NOT trust this thing to find a live wire before I drilled into the wall. Conclusions: - Unless you are buying this in part for the metal detection capabilities, go with a different scanner. Even then, you may still be able to find a separate stud finder and metal detector for about the same total price.
Date published: 2013-05-19
Rated 4 out of 5 by from Does what it says except on carpet This is a very good and solid wall scanner, it does what it says and is very accurate in finding studs behind drywall. It has a bunch of nice features and I prefer to use it over my cheaper Zircon stud finder. It has a nice opening so that you can easily mark the drilling location. A simple but very convenient feature. The display, lights, and tones are all very useful especially when working in tight locations or on ladders. I wanted to use this to locate floor joists under berber carpet in order to drive some screws to fix flloor squeeks. The manual says it can do such job. I was disappointed with its inability to detect those joists. It kept beeping like crazy and gave irregular results no matter which direction I ran. My Zircon stud finder also struggled and couldn't get this job done so I'm sure this has a lot to do with the type of carpet and thick undercarpet layer. I also tested the feature to detect wiring in the wall, and this works well as described. I did not test the feature of detecting rebar in concrete walls. I cannot give it 5 stars since I was expecting a better result for undercarpet floor joist detection.
Date published: 2013-04-24
Rated 1 out of 5 by from POOR SCANNER HIGH PRICE As much as i like Bosch products, their wall scanners are not accurate at all. My new $20 scanner scans better than this one. Thanx to Bosch scanner i put a nail into the BX (electrical wire in the wall) under the electrical box that was covered by a painting :-( The Bosch scanner didn't show any electrical in this area and it was a regular sheetrock wall... Ended up returning the unit and paying a huge repair bill... Stay Away from this scanner....
Date published: 2013-11-30
Rated 5 out of 5 by from A professional grade tool. If you are after something to locate studs for hanging a picture or mounting a TV, then this detector is overkill. But if you are a serious modeler, or need a full featured detector, this is the tool for you. I should warn you that there is leaning curve if you want to make full use of this detector. It presents a lot more information then a standard stud detector. There is the audio output like a basic stud detector. I find it annoying, but you may find it useful. It would be nice if it had a volume control, but at least you can turn it off. And the detector remembers for the next time you use it. It has a detector. It has a centering hole, with a ring around it that changes color to give a quick visual indication. Then there are two bar graphs that show "signal" strength, and centering. The centering graph is easy to use, but it needs to calibrate itself, so it is not going to show you the center of the stud until you hit the far edge. This is because it does not know how wide the stud is before then. But once it knows, you can back up the scanner and get a good center reading. Once you get used to it, you will love it because it gives you the true center. It works the same for other detection modes. The strength meter will give you an indication of how deep something is in the wall. Once you get a feel for it, it will let you estimate how deep or how big a metal object is. It is handy for telling the difference between a nail and a buried cable or pipe. The icons will tell you when it is detecting something for a different mode then you are using. If you pay attention, it can save you from cutting a wire. The mode button you select lights up to remind you what mode you are in, and there is a light you can turn on to illuminate the LCD display. Someone was thinking when they designed the scanner. I was able to try it on both plastered and drywalled walls. I was luck to have 2 walls where I know the location of the studs, so I could test how accurate the detector is. For the drywalled walls, it was very accurate. For plaster walls, the results were not as good. From past experience, I was surprised that it could detect the studs at all. It did much better when set to detect the nails fastening the lath to the studs. How well the live wire detector works depends on the wiring. If it detects the wire, it will give you a nice map of how it runs. But if you have BX, or knob and tube wiring, it may not detect the wiring. The metal sheathing on the BX effectively blocks the signal from the live wires. With knob and tube wiring, it will usually detect the wires to a switch if the switch is off, and their is a light in the circuit. If the switch is on, it may miss the wires. All non-contact detectors run into the same problem. Luckily it is rare to run into knob and tube wiring. I just happen to have a house that is over 100 years old, and has several different types of wiring. So it presents interesting challenges that you don't normally run into!
Date published: 2013-05-03
Rated 2 out of 5 by from High hope deflated. Had high hopes for this detector as Bosch makes great products. I liked the size and layout of the buttons and the backlight is great for low light areas. Thats about as far as the pro's went. The detector reads a green light as a you scan and flashes red when an object nears - confuses me, imo. it should be the other way around. When you approach an object the display "bar segments" increase until the center is found. Sounds great but I had so many false readings i didn't know what was behind the simplle 1/2" sheet rocked wall. I compared the same wall w/ a B&D dtector and had much better results. Bottom line save your $.
Date published: 2015-09-10
  • y_2017, m_3, d_20, h_19
  • bvseo_bulk, prod_bvrr, vn_bulk_1.0.0
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_57
  • loc_, sid_202850662, prod, sort_[SortEntry(order=RELEVANCE, direction=DESCENDING)]
  • clientName_homedepot
  • bvseo_sdk, java_sdk, bvseo-3.1.1
  • CLOUD, getContent, 27ms