- GDOT Automatic Insulation Oil Tester (80/100kV)
- GDZL-503 Automatic Tension Tester
- GDW-106 Oil Dew Point Tester
- GDW-102 Oil Dew Point Tester
- GDHL-200 Contact Resistance Tester (Automatic)
- GDH-100 Contact Resistance Tester (Manual)
- GDHL-200 Contact Resistance Tester (Automatic)
- GD6000A Capacitance & Tan Delta Tester