One of the services our lasers offer is the ability to both etch and engrave onto our products. There are many uses for this, including parts or drawing numbers, bend lines, barcodes or serial numbers and QR codes.
We have the ability to etch with either oxygen or nitrogen, the significant difference between the two being with oxygen you achieve a deeper and more distinctive cut, achieving a more pronounced edge. This can be seen by the image above [top ruler has been cut with Oxygen, bottom with Nitrogen].
Below is a few more examples: