Sennheiser GSP 370 Wireless Gaming Headset Review @ Vortez
 

Alongside that is a claimed 100-hour battery life, five times that of the GSP 670; an amount that almost seems unrealistic. You could go two or three weeks of reasonable usage between charging, something that’s pretty much unheard of in the wireless headset market.

https://www.vortez.net/review.php?id=1737