1500W Zener TVS in a through-hole axial package
It clamps transients at 113V max when the surge current hits, with a reverse standoff of 70.1V — meaning it stays out of the way below that DC rail voltage and only starts conducting when a spike exceeds 77.9V breakdown minimum.
The 70.1V reverse standoff is the maximum DC voltage the diode can block without conducting. If your rail sits at 48V or 60V nominal, this part gives you margin. The 77.9V breakdown minimum is where avalanche starts; the 113V clamping voltage is the worst-case peak the protected circuit sees during a 1.5 kW surge.