To find any manual for any Atlona product, simply go to Atlona.com, click the "Product SKU" drop-down menu (pictured below), and select your product.
If your product is not listed, please check the Atlona sitemap to find discontinued model numbers.
Once on your product's page, scroll down below the picture of your product, and click on the "Resources" tab. There you will find a link to your manual.
If there is no manual on the Atlona product page, or if your product is not listed on the sitemap, there is likely no manual available for your product. If you need help, please reach out to support: https://support.atlona.com/hc/en-us/requests/new