These are great for the World of Warcraft player who doesn't want to put their credit card information onto their account or have a recurring charge on their card/to their bank account. These cards can be purchased at just about any store and will allow you to play World of Warcraft for 2 months. There is no premium charged when you use one of these cards. You are still charged $30, which is equivalent to paying the $15/month charge twice, except it is upfront at once instead of once two months in a row. I used these exclusively when I was in high school and did not have a bank account, but was making money baby sitting. It was a great way to also make sure I was accountable with my money while also allowing me to play my favorite game for two months.