Broonel Heavy Duty Headphones Case / Cover With Built in Power Bank For Audio-Technica ATH-M50X Studio Monitor Professional Headphones / Audio Technica ATH-MSR7 / Audio Technica ATH-M50x With a built in power-bank & impact resistant soft core design, this case keeps your headphones protected and fully charged. Cases internal powerbank charges in 30 minutes via Micro USB charger, can charge majority of headphones twice on a full charge. Power Bank contains a 2500mah capacity UL certified Li-polymer battery with a Input / Output: DC 5V.1A. Single USB output, includes 50cm micro USB charging cable. Universal sized case, fits majority of popular Wireless Noise Cancelling Headphones.