I created these brushes to draw bike chains. There is a transparent version and a colored version (content id 2018997) depending on your needs.
Please note that the chains may not completely fit with each other at the two ends. (Please refer to the first 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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