2.5 mm headset, Headset with a 2.5mm headset adapter cord( 6ft long curly headset jack)
RJ9 Female 2.5mm Male Adapter | Plantronics Headset to Cordless Phone Connector Cable
Audicom 2.5mm Headset to Cisco Phone Adapter - 2.5mm to RJ9/RJ10 Converter for Cisco Unified Telephone IP Phones 7931G 7940 7941 7942 7971 and Plantronics MX10 Vista Modular Adapters (H25-CSB) - Newegg.com
Headset Buddy Female Headset to Male 2.5mm Plug Adapter - Convert 4P4C RJ9 to Phone Jack Cable Works with Plantronics, ATT, Cisco, Panasonic, Cordless & VoIP Telephones (RJ9-PH25) | Pricepulse
Plantronics Quick Disconnect to 2.5 mm Cable 64279-02 B&H Photo
Plantronics Mobility adapter 3.5mm - Walmart.com
Plantronics EncorePro HW510 with 2.5mm-Adapter
Mobile Headset Adapter for Plantronics M10/12 Amplifier
Plantronics QD to 2.5 mm Headset Cord for Cisco SPA IP Phones (64279-02)
Plantronics QD to 2.5mm Plug Adapter for H-Series Headsets
Male 2.5mm to Male RJ45 Adapter Cord
Headset Adapter Cable with 2.5mm Plug for Cisco | Business Telecom Products
Amazon.com: 2.5mm Headset to Cisco Phone Adapter - 2.5mm to RJ9/RJ10 IP Phone Jack Converter Compatible with Plantronics M22 Amplifier and Cisco Unified Telephone IP Phones 7931G 7940G 7941G 7942G 7945G (H25-CSA) :
Plantronics 2.5mm Headset Adapter Cable for iPhone and Smartphone