The 6.3 V rating is a common derating target for a 3.3 V or 5 V rail — the 1.3 V headroom above 5 V keeps the applied voltage below 80 % of rated, which is the typical tantalum reliability guideline.
18 mOhm ESR — ripple current and self-heating
The 18 mOhm ESR is the headline performance spec for this part. At 470 µF and 6.3 V, that ESR keeps the ripple current rating high enough for a switching-regulator output filter or a point-of-load decoupling bank.
The molded case (type: Molded) provides the mechanical integrity for those thermal cycles without the risk of conformal-coat cracking that can plague uncoated tantalums.
2917 (7343 Metric) — standard tantalum footprint
The package is the standard 2917 (7343 Metric) case, 7.30 mm x 4.30 mm with a seated height of 4.30 mm max. The manufacturer size code is E. This footprint is shared across the TPM series and is interchangeable with other low-ESR tantalum parts from Kemet, Vishay, and Panasonic — a layout designed for one will accept the others with no board change.