The DO-13 through-hole package suits point-of-use clamping on power rails in industrial or telecom equipment where board space is not the constraint.
Peak pulse power and voltage ratings for the BOM
The 261V clamping voltage sets the maximum voltage the downstream circuitry sees during a transient event; a 171V breakdown minimum ensures the diode starts conducting before the rail exceeds its safe operating area. The 5.7A peak pulse current rating at the same waveform gives the current-carrying capacity during the surge.