This digital voltmeter has been specially designed to incorporate features requested by educational laboratories. Negative scale to clearly demonstrate reverse polarity .Zero adjustment. • Range: 0-20V D.C. • Resolution: 0.01V D.C. • Accuracy: ±2% • Internal resistance: Approx 1oMohm • Super strong high grade ABS case • Protective display window • Long battery life • Colour coded and shrouded 4mm sockets • Screw locking battery compartment • Theft deterrent “SCHOOL VOLTMETER” printed on model • Dimensions: 95 x 90 x 75mm • Large bold 14mm digital LCD display • Power: 1 x 9v ‘PP3’ size battery included