I created these brushes to draw bike chains. There is a transparent version (content id 2018995) and a colored version depending on your needs.
Please note that the chains may not completely fit with each other at the two ends. (Please refer to the image below.)
To solve this issue, I would recommend you to use the brush on a vector layer. You can then adjust using ‘object function' to make a perfect ring.
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My example of use:
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