This is the link to get all (most of them) Cisco Visio stencils. https://www.cisco.com/c/en/us/products/visio-stencil-listing.html#anchor813
There is no AIR-AP-BRACKET-2 visio stencil listed.
And, I don't remember seeing a Cisco document with AIR-AP-BRACKET-2 dimensions listed either.
Try reaching out your Cisco rep to see if they can help you out.
Jagan Chowdam
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