The RSH-1203P-240D Type 1 Surge Protective Device (SPD) is a robust surge protector for three-phase 240V delta commercial HVAC. It safeguards equipment, enhances power quality, and reduces EMI/RFI noise. Compact and weatherproof (NEMA 4X), it clearly indicates protection status and features durable GDT technology with no maintenance required. Uses long-lasting gas discharge tube (GDT) and thermally-fused metal oxide varistors (TFMOV) technology. Includes dual diagnostic LEDs and audible alarm. Type 1 SPD, NEMA 4X, and IP66 rated.