Buy two get one free is a joke. Don't fall for this scam like I did. You pay for your 2 sets and they send you a rebate form. Pay attention, the rebate form has to be completed and returned within 30 days. However, the rebate costs money! Yes, you have to pay more money to get that "free" set. They don't advertise a 30-day rebate offer. They advertise buy two, get one free. False advertising.