The Hypertherm 003149 Relay is a 120 VAC Double Pole Double Throw (DPDT) pilot arc relay used in Hypertherm plasma cutting systems, particularly the HPR130 Auto Gas model. Product Details & Compatibility Voltage Rating: 120 VAC. Pole and Throw: 2 Pole, Double Throw (DPDT). Contact Material: Silver Cadmium (Ag Cd). Configuration: Normally Open/Normally Closed (N0/Nc). Function: It is a pilot arc relay.