on september 6, 2006 the developer tools group (the working name of the not yet spun off company) of borland software corporation released single-language editions of borland developer studio 2006, bringing back the "turbo" name. the turbo product set included turbo delphi for win32, turbo delphi for .net, turbo c++, and turbo c#. there were two variants of each edition: "explorer", a free downloadable flavor, and a "professional" flavor, priced at us$899 for new users and us$399 for upgrades, which opened access to thousands of third-party components. unlike earlier "personal" editions of delphi, "explorer" editions could be used for commercial development.