10-pk of Batteries for Plantronics W440 & W740 Series Wireless Headset Compatible with the following devices Savi W440 Savi W440-M Savi W740 Savi W745 Savi WH500 PN: 83359-01 PN: 83372-01 PN: 83542-01 PN: 86507-01 PN: 83356-01 ...