TVS diode for 256V rail protection
The 1.5KE300CA: The 256V standoff makes this a fit for 240V DC power rails or AC lines where the peak voltage stays below 256V under normal operation.
Through-hole DO-201AA (DO-27) axial package, supplier device package DO-201. The axial leads suit point-to-point wiring or PCB through-hole mounting with 0.040-inch diameter leads — standard for this power class.
The 1.5KE series is a mature, widely stocked line — cross-reference to other 1500W bidirectional TVS in DO-201 is possible but requires verifying the standoff and clamping voltages match your protection threshold.