This TAJT225M020RNJ is a 2.2 µF tantalum capacitor rated at 20 V, with ±20% tolerance — the nominal capacitance is the centre of the distribution, so a BOM calling for 2.2 µF at 20 V gets a part that holds that value across the tolerance band. The 6 Ohm ESR at 25°C sets the self-heating under ripple current; for a 20 V rail with 100 mA ripple, the I²R loss is 60 mW — negligible for this package, but worth checking if the capacitor sits in a high-ambient area on the board.
Housed in a 1411 (3528 Metric) molded case, size code T, measuring 3.50 mm x 2.80 mm with a seated height of 1.20 mm max — this is a low-profile part that fits under a 2 mm board-to-board clearance.