Crydom"s family of SPST-NO relays achieves one of the highest power switching capability in a PC-mounted air-cooled package. Advanced features include exceptional steady state current, plus ultra-high surge ratings.* Operating Temperature Range:** –30°C to 80°C. ** Isolation Voltage (VAC):** 4000\. ** Available Option:** -B — Normally closed (CX240D5 only). ** M Series:** MP packaging (relay is inserted into plastic case filled with epoxy).