The Z-150 is a desktop modem which is not portable. It sits on the desktop and has its own screen (does not require a TV). It cannot be plugged to an external monitor nor does it have batteries. It is designed to sit on your desk. The viodeo quality is of very high quality and is designed to go through firewalls with both incoming and outgoing calls.
The Z-340 is a portable device and has its own screen as well. It can be plugged to an external video monitor such as a TV. It also has wifi capability and can be run on batteries. It is designed to be mobile, taken from one place to another. A commonly misunderstood feature is whether it operates on a cellular network. It only works with wifi, not cellular, like a Blackberry or the like.
The Z-Ojo is similar to a Z150, except that the screen is more vertical.
The Z-PC-100 is software that is downloaded to your PC. It does not work on a Mac and it requires a webcam to enable video communication.
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