It's two coaxial connectors for hooking up a cable box or modem, in addition to a serial port for your printer or other peripheral unit. It also offers two network ports so that you can connect the unit into a server, a Wi-Fi router, or another device that requires a https://mixed-martial-arts61593.popup-blog.com/33043535/how-much-you-need-to-expect-you-ll-pay-for-a-good-ups-800va