What the ratings mean for your protection design
The 1.5KE160-B: This is a 1500W peak pulse power TVS diode (1.5 kW at 10/1000 µs waveform) in the 1.5KE series. The 136 V reverse standoff voltage means it starts clamping above that level, protecting a 120 VAC or 130 VDC rail from transients. Breakdown is guaranteed at 144 V minimum; the clamping voltage is 229.95 V maximum at the 6.9 A peak pulse current. That clamp voltage is what the downstream circuitry must survive — a 200 V-rated MOSFET would be marginal here. Single unidirectional channel in a DO-201AA (DO-27) axial-lead package. Through-hole mounting suits point-to-point wiring or terminal blocks where a surface-mount TVS won't fit.
Sourcing this obsolete part
Since Littelfuse has discontinued the 1.5KE160-B, new inventory comes through independent surplus or broker channels.