Saramonic WITALK-BP Rechargeable Lithium-Ion Battery for WiTalk (3.7V, 1200mAh) For WiTalk Wireless Intercom Headsets, For WiTalk-Hub Base Station, Quick-Change Battery, Up to 18 Hours for DRH and SRH Headsets, 5 to 10 Hours Master Headset, 2.5 to 5...