The ET 7 has a remote transmitter, located where the probes will be located. A reciever is set up within 100 ft.
The probe length is is over 8" with usable 6". The cable is 40".
Even though it's a cooking thermometer there are selections for beef, lamb port, ect. Thats on the top part of the screen. The middle scrreen is for the probes. It does not display both probes at the same time. If you depress the S1/S2 button it switches between the two probes. Depressing and holding the S1/S2 button for 2 seconds allows the probes to switch automatically, but only for a few minutes. No temp change for a long period of time displays --- . Once it sees a temp change it comes back on. (Kinda like a screen saver?)
The bottom part of the screen is a clock and or timer. I use mine as a clock.
http://www.maverickhousewares.com/et7.htmI bought ours on ebay (new) for $38. That included shipping.
EDIT: Yes I leave it on all the time. I actually have probe one set with an alarm setpoint of 190F and probe two set at 165F. (water in/out of HWH)