SUNDELY Single Ear Boom Mic Headphone with Volume Control 4-pin RJ9 Modular Connector for General Electric GrandStream Hybrex Intertel Interquartz Iwatsu Lazerbuilt MITEL NEC Orchid PLT Telephone /IP Phone Single Ear Boom Mic Headphone with 4-pin RJ9 Modular Connector for Telephone /IP Phone 4-pin RJ9 Modular Connector, Adjustable Boom Mic, Volume control General Electric 2-9451, 2-9490, GrandStream Budgetone 101, Budgetone 102, GXP280, Hybrex DK1-21, DK2-21, DK3-21, Intertel 8520, 8560, 8600, 8620, 8660, 8662, 8690, Interquartz Gemini, Gemini 9330-AV, Gemini 9335 CLI, Gemini 9335-AV, Speakerphone, Enterprise Speakerphone, Enterprise Discovery, Interquartz 98380 Iwatsu IX 12KTD-3, IX24KTD-3, Lazerbuilt Prestige 905K, 906K, 907K, MITEL Superset 4000 Series, 4015, 4025, 4125, 4150, 5000 IP, 5010, 5020, 5020i, 5040i, 5050, 5055 IP, 5055 SIP, 5140, 5201, 5207 IP, 5210 IP, 5212, 5215, 5220, 5224, 5230, 5235, 5240, 5550 IP, Orchid DBT 2000, DBT 3000, PLT A100, S10, S11, S12, S50, SP-02, SP-04, SP-05, T10, T20, T50, T100, T110, PLX-400, PLX-500 NEC Electra Elite DTerm, Series E, Models DTU-8, DTU-8D, DTU-16, DTU-32, DTU-32D, DPT-8, DPT-8D, DPT-16, DPT-16D, DPT-32, DPT-32D, DTH-8, DTH-8D, DTH-16, DTH-16D, DTH-32, DTH-32D, Dterm Series i, Aspire, DT310, DT330, DT700, DT730, DT750, DSX, DTL, DTP, DTR, DTU SERIES