Coulomb Meter is a useful tool and behaves similar to a Digital Electroscope.  It acts as a digital electroscope measuring positive and negative charge on the digital LCD display. It can be charged by contact or by induction by bringing a charged body up to the 25mm collecting plate. An electroscope will deflect its vane but this instrument shows the charge digitally in Coulombs up to 1999 nano Coulombs, Accuracy +/- 10 nano Coulombs.