As maxman wrote, press the EXPN key and then the screen will tell you to press the "1" key to turn the throttle off.
Press the "EXPN" key. You will get two choices on the screen. I believe that choice "1" is the one you want.
Edit: And I believe that there are 4 AAA batteries in there.
I have an NCE power pro radio throttle that I want to turn off when I am done. It shuts itself off after a while but uses up battery power in the meantime. This is no big deal but I think there is a way to turn it off with the keypad. Removing the 2 AAA batteries involves removing a non captive screw and is not a practical solution for me.
73
Bruce in the Peg