The lithium-ion XL-B18650 is Sound Devices’ proprietary battery designed specially to power the A20-HH handheld microphone. At 10mW, the XL-B18650 has an impressive runtime of more than 10 hours, so your A20-HH mic will be ready for the encore.
The USB-C connection on the A20-HH can be used to charge the XL-B18650 battery while it’s on board the unit. Alternatively, the battery can be removed and charged externally via third-party charging stations.