Request Headers: specify HTTP headers that CDN servers will add to requests to the origin server
Set custom HTTP Headers for CDN servers to add to requests to origin.
Go to CDN Resources tab -> Settings -> Show Advanced Settings -> HTTP Headers -> Add Request Headers.
The Header name field can contain letters (A-Z, a-z), numbers (0-9), dashes (-) and underscores (_).
The Value field can contain letters (A-Z, a-z), numbers (0-9), dashes (-), underscores (_), slashes (/), colons (:), equal (=), dots (.), and spaces.
If your Value field has several words you can add one space between two words. The Value field can't start or end with space.