What this part number is
The 1FK7042-5AK71-1TH2 is a Siemens 1FK7 compact synchronous servo motor carrying the brand-level catalog entry listed as a 1FK7 COMPACT SYNCHRONOUS MOTOR in the active catalog records. Servo motors in this class are the rotor-and-stator element of a closed-loop drive system — paired with a SINAMICS-class drive and resolver or absolute encoder feedback, they execute the position, velocity, and torque profiles that feed machine axes from packaging lines to machine tools.
Where it fits in a machine and what the ratings confirm
Sourcing a synchronous servo motor is driven by the matching motor-module firmware on the drive side — the order code suffix determines shaft, holding brake, encoder, and connector option, so the BOM line must match the suffix string before the motor is committed to the cabinet layout.