Special order item. Call for availability. 

Plantronics SHS 2391-11 USB PTT Push-To-Talk to TA6MLX connector. . Compatible with standard USB drivers. The Push-to-Talk switch enumerates as button 1 of a single button game controller. Used with training simulators, VoIP communications and speech recognition anywhere that high quality USB audio with push-to-talk switching is required. Plantronics SHS 2371-11 is stereo only works with Dual Channel headsets such as the HW261N-DC or Left channel only headsets and other Models like SHS 2069-01 & SHS 2378-01.

See Plantronics SHS2371 datasheet 

*Important Note: Due to the manufactures policy, this is a special order headset.  It's not returnable, non-refundable.  If it's defective, Plantronics will replace it for you under warranty

Old Poly part # 92371-11

New HP part # 8K718AA#AC3