Amazon.com: Sennheiser CSTD 01 Standard Headset Connection Cable for Direct Connection of Specific Phones : Electronics
EPOS/SENNHEISER CSTD 01 ED to RJ9 Standard Bottom Cable 1000836
ATC 1
Sennheiser CSTD 01 cable - 888VoIP
Amazon.com: Sennheiser Enterprise Solutions CSTD 08 (005365) Standard Headset Connection Cable, Easy Disconnect to Modular Plug RJ 9, Coiled Cord, Code 08. for Direct Connection of Specific Phones : Electronics