We use Stripe (https://stripe.com/) as our payment processor, and do not store any credit card information in our own database. The initial transaction that sends the credit card information to Stripe is done securely. Thousands of trusted companies use Stripe to handle their transactions. You can read more about Stripe's security here.
At Concert Window, we take online financial safety very seriously. Whilst Stripe may be unknown to some online consumers, it is one of the leading payment structure applications on the internet, used by thousands of global companies each day including Virgin, Reddit, Twitter, The Guardian and Foursquare. By using Stripe, we are in no way compromising your online safety.