What you're looking at
The ABB ACS800-U1-0006-5+K466+L502+L503+P901 is a wall-mount industrial AC drive in the ACS800-U1 frame, factory-built with four option suffixes — +K466, +L502, +L503 and +P901 — that have to be ordered together as one line item. It sits in the ABB Motor Drives line under Drives, so it inherits the ACS800-U1 mechanical footprint and control architecture rather than a later ACS880 platform.
Second-source and the ACS880 question
The successor platform is ACS880-01; the same-frame wall-mount at the listed current class is ACS880-01-07A6-5 at 6.35 kg. Footprint and depth carry forward between the ACS800-U1 and the ACS880-01 at the same current class, but the ACS880-01-07A6-5 ships with the new control panel, revised terminal layout and updated firmware base — wiring is the same family, but fieldbus adapter slots and parameter structure are not a direct image swap, so plan for a parameter migration, not just a mechanical drop-in.