The Siemens 3VU2935-0J is a set of back screw connections for the 3VU2.4 and 3VU2.5 circuit breakers — three parts per side, so you need two sets for a complete line-side and load-side termination on a three-pole breaker.
Integration note for panel builders
These back screw connections mount directly to the terminal studs on 3VU2.4 and 3VU2.5 breakers, converting the standard front-connect terminals to rear-exit wiring. The three-piece set covers one side (line or load); order two sets per three-pole breaker if you need both sides wired to the rear.
