The SMCJ series is designed specifically to protect sensitive electronic equipment from voltage transients induced by lightning and other transient voltage events.
Datasheets by Manufacturer
SMCJ78C — Thinki Semiconductor — Transient Voltage Suppressor
SMCJ78 — EIC Semiconductor — SURFACE MOUNT TRANSIENT VOLTAGE SUPPRESSOR
SMCJ78AQ — Diodes Incorporated — AUTOMOTIVE TRANSIENT VOLTAGE SUPPRESSOR