If you say serial, some might think that can't be what they have. I could be mistaken on this, but I'm pretty sure. It's been a long time since I've messed with parallel/serial cables. A DB25 cable is generally a parallel cable (for printers, scanners, etc). A DB25 extension cable supports parallel and serial connections. So calling it a 25 pin serial cable could easily cause confusion and for someone to think it is not the same as a DB25 extension cable. FYI.