You will be receiving one of these per day during the November login campaign. I do not know if they will be offer during additional campaigns. You trade them to one of the Gobbie Mystery Box Vendors that you will find scattered thru all 3 Nations, Jeuno and Whitegate. I will paste a link below for their locations.
Simply approach the Gobbie, talk to him first to start the mini quest, then you can trade a key to him. You can receive anything from a flint stone to a very high level 107 rare/ex piece of equipment - it is completely random. You will start earning points each day after talking to the Gobbie and be able to talk to him to open dials. You can use as many Special Gobbiedial Keys per days as you want - but if you use points to open the Special Dials, you can only do that once per day. Skyfiredancer (talk) 01:38, November 24, 2014 (UTC)