How secure is your payment system? We use the payment systems PayPal and BrainTree (which is owned by PayPal) for processing all credit card and debit card payments. We accept all major credit cards, including American Express and Discover. Have more questions? Submit a request 1 Comments Date Votes 0 Damian Valdes December 22, 2017 22:04 Where can I find an invoice / receipt? Please sign in to leave a comment.