The Keithley 6517B Electrometer/High-Resistance Meter is the worldwide research laboratory standard for sensitive measurements that provides reliable measurements of current levels down to 10 aA (10 x 10¹⁸A), charge levels down to 1 fC, and the highest resistance measurements available up to 10¹⁸Ω.
Features:
Capable of measuring voltage range up to 200V with input impedance exceeding 200 TΩ
6-1/2 digit high-accuracy measurement mode
Built-in ±1000V voltage source