Electrostatic Field Meter Lutron

See data sheet here

FEATURES
* Professional precision STATIC Voltage meter with 0.001 kV resolution, digital display, battery operated.
* LSI – circuit provides high reliability and durability .
* Operation directly.
* Measurement range : -19.999 kV to +19.999 kV.
* High voltage alarm : +/- 18.000 kV.
* ALARM setting : 0.010 kV to 18.000 kV.
* Data hold , Record ( Max. , Min.).
* LCD with green light backlight, easy reading .
* RS232 / USB Computer interface.
* Built-in low battery indicator.
* Power : DC 9V ( 006P ).