Sealey VS0272 Pocket Brake Fluid Tester

Electrolytic tester.
Integrated circuitry checks moisture content of fluid by measuring the electrical resistance and comparing it with acceptable limits.
Easy calibration check using water.
Three LED read-out.
Just switch on and insert probe for immediate result.
Red LED warns when battery is low and needs replacing.
Uses 1.5V AAA battery (supplied).