10-level conductivity detector

This handheld device provides a qualitative visual indicator of the conductivity of different solutions, acids or salts. Two brass probes can be touched to a solid substance, or immersed in a liquid, to show conductivity on green LEDs that range from 1 to 10. Each probe is 53mm long with a diameter of 3mm. Overall length of the meter and probes together is 14cm. Includes a 12V battery and operating instructions.