Rechargeable Design: Don’t miss a call, webinar or video conference again. Synergy Digital’s 82742-01, 84598-01, 204755-01 Battery Combo Pack Compatible for Plantronics Systems automatically recharges when your headset is in the charging cradle..Superior Performance: Made of Lithium Polymer, each 3.7 volt, 140mAh battery will last all day so you can keep your headset by your side at all times. Simply place it back in the charging cradle when leaving the house or office, or retiring for the night..Long-Lasting Use: Each Ultra Hi-Capacity SDHS-P902 Battery is made with high-quality Japanese cells to ensure long-lasting use. In fact, Lithium Polymer batteries have over a 20% higher energy density than Lithium-Ion batteries..Combo Pack: This combo pack from Synergy Digital includes two SDHS-P902 batteries, allowing you to charge up two wireless headsets at once if needed. If you only have one headset, simply keep a spare battery on hand for future use..100% compatible with your Original Battery - 3 year warranty. Made with high quality Japanese cells.