These are not QR codes, they are called Datamatrix codes. They can be made very small and can be applied with minimal contrast so it would work well on products with surface coatings of different colors. Ideal for cutting tools or toolholders. They can be laser or electro etched and be applied with dot peening. You can even print them on fluid-resistant metallic label tape with high strength adhesive with a simple sub-$100 label printer.
In Google's latest version of their Chrome mobile browser they include a Datamatrix-compatible bar code scanner. Every smartphone can now become a 2D bar code scanner. While the Datamatrix code cannot hold as much data as a QR, it can contain a shortened URL. You could put a code on your product that opens a webpage or a PDF catalog page for that item. In our example, scan the code on the left to open an interactive Dashboard for a milling tool assembly.
Another advantage of the Datamatrix is that it will still work when damaged. We purposely scratched the code on the right at it still scans.
You can make a lot of vital information instantly available on the shop floor with use of these codes. Think of the possibilities.
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