Industrial 66306-04 66302 21A1690 21A1683 9601 Speakerphone

The Rolmphone RP612S gray speakerphone is a two‑way unit for the Rolm 300/600 family, delivering hands‑free conversations alongside a standard handset. Built for Rolm desk stations, it includes a speaker and microphone so you can answer and place calls from the speakerphone or switch to the handset as needed. Associated identifiers for this model include 66306-04, 66302, 21A1690, 21A1683, and 9601, reflecting its Rolm/Siemens lineage. The RP612S is documented as compatible with Release 9005 systems (Feature 52/Desktop) and Release 9006 systems with SLMR3 cards, ensuring compatibility with those Rolm environments. Color is gray, consistent with other Rolmphone 300/600 accessories, and the RP612S is described in catalogs and refurb listings as a speakerphone suitable for replacement or upgrade in older Rolm networks. When used on supported systems, you can press the primary line key or the SPEAKER key to obtain a dial tone, making it possible to use either the handset or the speakerphone for conversations.