Surge-Trap® Monobloc Surge Protective Device (SPD) ST Series is a highly cost effective, no-fuse, fail-safe surge suppressor featuring Mersen’s TPMOV® technology inside – no need for additional overcurrent protection. All catalog numbers are UL 1449 5th Edition approved, DIN-rail mountable, with visual indicator and a small footprint. A remote indicator provides status for local or remote indication. A high short circuit current rating makes it suitable for most industrial control panels.