Standard Resistor is exclusive used for calibration of grounding resistance tester, equipotential tester and other instrument. 1. Model No.: ETCR3900 2. Resistance Range : 0.001Ω~100KΩ 3. Connection Wire Method: 4-wire method 4. Temperature Coefficient : ±25ppm 5. Test Line : 4PCS 6. Power : 1/2W