This is a mozilla a Experimental technology .
HTTP 402 Payment Required It's a nonstandard client error status response code , Reserved for later use .
This status code means that the client can only process its request after payment . first , It's for enabling digital cash or （ tiny ） Payment system , It will indicate that the requested content is not available until the client pays . however , It's not a standard usage Convention , Different entities can use it in different contexts .
HTTP/1.1 402 Payment Required Date: Wed, 21 Oct 2015 07:28:00 GMT