Adapter Converter Mobile Smartphone iPhone Samsung Headset Headphone 3.5MM 2MM Plug to RJ9/RJ10/RJ12 4P4C Plug for Most Office IP Telephones Cisco Avaya + Microphone Channel Settings - Walmart.com
2.5mm Female to 3.5mm Male Headset Adapter Headphone Jack Converter Supports Hands-free Microphone A6W for LG Rumor Touch LN510, Spectrum 2, Splendor, Sunset, Thrill 4G - Walmart.com
Amazon.com: VoiceJoy Standard 3.5mm Jack Smartphone Headset Adapter Cable Converter to RJ9 Plug for Cisco Unified Office Telephone 7970 7940 7941 7942 7971 etc : Electronics
RJ9 Female 2.5mm Male Adapter | Plantronics Headset to Cordless Phone Connector Cable
Plantronics Adapter Cable (QuickDisconnect - 2.5mm) for Polycom IP 320, 321, 330, 331, Panasonic, AT&T, RCA,
Amazon.com: 3.5mm Plug Adapter Converter to Quick Disconnect QD Cable for Plantronics Headset Headphone Work with Smartphone Mobile Phone Laptop Computer PC Mac with Single 3.5mm Jack : Electronics
Headset Buddy PC35-PH35G - Gold Plated PC Computer Headset to 3.5mm Smartphone Adapter