The Schneider Electric A9XPC812 is a cuttable comb busbar from the Acti9 range, designed to distribute power from a 3P+N incomer to outgoing ways in a DIN-rail enclosure. It gives you one 4-pole incomer way (N + 3 L) and eight outgoing ways split as N + L per way, with 9 mm pitch between phase and neutral and 18 mm between phases on the outgoer. That layout matches standard 18 mm modular MCB/RCD footprints, so you land the busbar onto the tunnel terminals and snap the breakers on top — no extra wiring between phases.
This busbar mounts horizontally on top of tunnel-type terminals, so it sits above the breakers rather than behind them. The 218 mm width and 27 mm depth fit inside a standard 12-module DIN-rail cutout; the two included end pieces cap the exposed ends per IEC 61439-1 requirements. Pollution degree 3 rating means it's fine for the usual control-panel environment — some dust, some humidity, no condensation — without needing conformal coating. The 960 °C glow-wire resistance (30 s per IEC 60695-2-1) covers the fire-safety angle for most industrial and commercial specs.