What the line carries
The 1FK7042-5AK71-1GB3 is a Siemens 1FK7-series servo motor, the synchronous brushless type used with a SIMOTION or SINAMICS drive to close a position/speed loop on a machine axis. It sits in the Motors & Motor Controls > Servo Motors line as a compact, high-dynamics stator for indexing tables, small feed axes, and packaging or converting shafts where the controller commands torque, not just on/off rotation.
Sourcing posture for a line-down spare
For a line-down scenario, the realistic path is to specify 1FK7042-5AK71-1GB3 by full order code against an RFQ — quote back the quantity, the desired date-code window, and any resolver/encoder variant the existing drive commissioning expects, so the seller can match the unit to the panel on the floor rather than substitute on the assumption of equivalence. Quoted-to-order is the working posture here, with current pricing and lead time confirmed at quote time against the actual stock the independent channel holds.