Surge clamp for 120 V rails
Its 500 W peak pulse power rating (10/1000 µs waveform) means it can absorb a 2.3 A surge before the clamping voltage hits 214 V max — enough for most industrial and telecom secondary-side protection.
Standoff voltage and clamping ceiling
The 120 V reverse standoff voltage is the DC bus level the diode sees during normal operation — it will not conduct until the breakdown threshold of 133 V min is crossed. The clamping voltage of 214 V max at the peak pulse current tells you the maximum voltage the downstream circuitry will see during a surge event. That 214 V ceiling is the number to compare against your load's absolute maximum rating.
That means the BOM position is not at risk of a sudden last-time-buy scramble. The suffix typically indicates lead-free / RoHS-compliant finish, though the evidence does not carry an explicit RoHS statement — confirm with the datasheet if your process requires a formal declaration.