The TAJB475M020H is a 4.7 µF molded tantalum capacitor rated at 20 V, making it a fit for 12 V supply bypass or bulk storage where the derating margin keeps the applied voltage under two-thirds of the rating.
The 3 ohm ESR at 20 V sets the ripple current ceiling — in a switching regulator output, the self-heating from ESR limits the AC current the cap can carry without exceeding its temperature rating.
The 1411 (3528 Metric) / 1210 case, 3.50 mm x 2.80 mm footprint, sits low at 2.10 mm seated height — the molded body is tough under hot air, but the tantalum anode is polarity-sensitive: get pin 1 orientation right before reflow.