The Spectre SV-4 is Ironlimb's covert operations arm, engineered with acoustic-dampened servo housings that reduce operational noise to under 18 decibels — quieter than a human heartbeat at arm's length. The forearm contains three concealed compartments: a slim-profile tool cavity rated for lock picks and bypass tools, a document/data-chip sleeve, and a spring-loaded injector housing for up to two syringes. The entire arm is signal-shielded with a Faraday-weave chassis layer, preventing electromagnetic scanning from detecting internal contents or broadcasting a cyberware signature to passive scanners.

The SV-4 is officially marketed to licensed investigators, corporate espionage consultants, and executive protection specialists, but its real customer base is well understood by anyone on the street. Ironlimb maintains plausible deniability through careful licensing language, but the arm's compartment specifications and signal-dampening capabilities make its intended use cases obvious. In the Spire tiers it's used by fixers and corporate intelligence operatives; in lower tiers it's the arm of choice for couriers who move things that shouldn't be moved.