Must Revalidate HTTP Cache-Control

   Indicates that once a resource has become stale (e.g. max-age has expired), a cache must not use the response to satisfy subsequent requests for this resource without successful validation on the origin server.

Cache-Control Header Max-Age

   Specifies the maximum amount of time a resource will be considered fresh. Contrary to Expires, this directive is relative to the time of the request. this website is having max-age=7200 secs.

Cloudflare

   Cloudflare, Inc. is an American web infrastructure and website security company, providing content delivery network services, DDoS mitigation, Internet security, and distributed domain name server services