The 40.2 V reverse standoff voltage means it sits across a 36 V or 40 V nominal rail and stays out of conduction until a transient drives it into breakdown at a minimum of 44.7 V.
Bidirectional clamping — one device covers both polarities
With a single bidirectional channel, the 1.5KE47CARL clamps positive and negative transients symmetrically. That saves a diode count on AC-coupled lines or bipolar supplies where you would otherwise need two unidirectional TVS devices back-to-back. The capacitance at 1 MHz is 1025 pF — high enough to add a small signal load on fast data lines, so this part is better suited for power protection than high-speed I/O.
The base product number is 1.5KE47, so the same die and package are used across the suffix variants (tape-and-reel, cut-tape, bulk).
Package and mounting — through-hole for serviceable designs
The DO-201AA axial-lead package is a standard through-hole form factor. It is a straightforward hand-solder or wave-solder part; the axial leads let you bend and trim to fit existing PCB hole patterns.