This is business::onlinepayment::payflowpro, an business::onlinepayment backend module for paypal payflow pro. it is only useful if you have a merchant account with paypal payflow pro: https://www.paypal.com/cgi-bin/webscr?cmd=_payflow-pro-overview-outside

business::onlinepayment is a generic interface for processing payments through online credit card processors, online check acceptance houses, etc. (if you like buzzwords, call it an "multiplatform ecommerce-enabling middleware solution").