This TPSB107K006R0400 is a molded tantalum capacitor from KYOCERA AVX's TPS series, offering 100 µF capacitance with ±10% tolerance at a rated voltage of 6.3 V. The 400 mOhm ESR is the key parameter for ripple current handling — in a 3.3 V or 1.8 V rail filter, that ESR limits self-heating and keeps the capacitor within its thermal budget during continuous operation. The molded case in the 1411 (3528 Metric) / 1210 footprint with a seated height of 2.10 mm max fits standard surface-mount assembly. Size code B means the footprint is consistent across the TPS family — if you've placed a B-size AVX tantalum before, the land pattern is the same.
The molded case keeps the element sealed against moisture and vibration.