The TAJB157M004RNJ: This is a 150 µF tantalum rated at 4 V with a 1.5 Ohm ESR — the capacitance and voltage are the first check for bulk decoupling on a 3.3 V or 1.8 V rail, and the ESR tells you how much ripple current the cap can handle before self-heating becomes an issue. The ±20% tolerance is standard for tantalum — the actual capacitance at 4 V bias will sit near the nominal, but derate the voltage by 20% in design for reliability (3.2 V working max in practice).
B case, surface-mount — fits the 1210 footprint
Manufacturer size code B, which maps to the 1411 (3528 Metric) or 1210 case — 3.50 mm x 2.80 mm footprint, 2.10 mm seated height. Surface-mount, supplied on tape and reel — the reflow profile follows standard tantalum recommendations; no special bake unless the moisture sensitivity label says otherwise.