Cameron Sino 240mah Battery For Plantronics C65,cs351,cs361,cs50,cs510,cs520,cs55,cs65,hl10,savi 410/420/710/720,wh300,wh350 - Digital Batteries - AliExpress
Lot of 2 Plantronics Spare Battery 65358-01 for S510 CS520 W410 W420 W710 W720 | eBay
202599-03-A1 Plantronics Spare Battery for CS510 and CS520 (Refurbished)