So in order for my web application to tell Nginx not to cache a page what header response should I be sending ?

X-Accel-Expires: 0
X-Accel-Expires: Off

I read here it should be "OFF" https://www.nginx.com/resources/wiki/start/topics/examples/x-accel/#x-accel-expires

But it does not mention if numeric value "0" has the same effect Nor does it mention if the "off" value is case sensitive or not.

I am hoping case sensitivity does not matter.

http://www.networkflare.com/