Siemens 3RA2933-2BB1 — SIRIUS electrical and mechanical wiring kit, including mechanical interlocking, for a star-delta (wye-delta) contactor assembly in size S2. Screw terminal connection. The spring-loaded equivalent is 3RA2933-2BB2; for a reversing starter assembly of the same size see 3RA2933-2AA1 and 3RA2933-2AA2.