This product is either discontinued or we cannot get that from suppliers.
Poly Plantronics Spare Travel Charging Case 204500-108, Black, Voyager 5200, Travel Charging Case.
The perfect accessory for storing, protecting, and recharging your headset. The case’s internal battery can recharge the Voyager Legend headset twice for up to 14 hours of additional talk time (up to 21 hours talk time total).