What this order code actually ships
The LXMMCRA0A00S100 is a guide rail set — the mechanical track the Lexium MC12 multi carrier modules ride on — not a drive or motor itself, and Schneider Electric lists it under spare-parts accessories for that family (cite:, cite:, cite:). It's sold one set per package, so a single order code covers the rail you need for one carrier assembly (cite:). The guide rail installs through a full 360° of orientation, which is the whole reason this version exists — the carrier can be mounted in any plane to follow the machine's curve rather than forcing the layout into a straight axis (cite:).
Footprint and what it means in the cabinet
The rail runs 10.3 in (260.7 mm) long, so the cut-out and the clearance behind the mounting surface must accommodate that length before you commit the BOM line — a junior wiring the first time should dry-fit the rail in the panel and check the bend radius against the carrier's spec before bolting down (cite:).