There is vessel view link and vessel view mobile
Vessel view mobile allowed you to see some of your motor infos w/o the ability to control anything.
Vessel View Link gives you the ability to view all the infos from the motor (more then you ever need) and the ability to control also. You can use troll control, tow control et ... all this from your lowrance or simrad unit and your Mercury motor. Vessel View is a box that link the mercury and the Navico unit all on a NK2000 network.