Klarna is a payment provider, with which you can comfortably pay with a money transfer within 14 days, or pay in installments.
When you buy tickets at Ticketmaster.fi, you simply select "Klarna" as your method of payment.
If you select payment by invoice, you will receive information from Klarna about how to pay for your tickets.
For more information about Klarna, please refer to Klarna.com.
Pleace notice that ticket purchases are binding when you have chosen Klarna as payment method.