This Spare Headset is NOT compatible with W440 & W740. This is the spare headset If you lost or broke your Plantronics Savi headset. Plantronics Savi W440/A & W740/A Wire less. Genuine Plantronics WH500/A Spare headset for the Plantronics Savi W440/A, W440-M/A, CS540/A.
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