12.How long is the battery life for one time? How many times can the charging case charge the earbuds?

If the FW1 plays music at an output acoustic pressure of 90dB (normally the maximum acoustic pressure without damage to hearing = 6-7 levels of iPhone volume):
1. Playing music in aptX codec, the battery life of the master earbud is 5 to 6 hours;
2. Playing music in AAC codec, the battery life of the master earbud is about 7 hours;
The above time explanation is the battery life of the master earbud. After the master earbud is turned off, the slave earbud can continue to play for about 2 hours. Therefore, to swap the master and slave earbud when using it can extend the endurance time.

When the two earbuds run out of power, the charging case can provide a full charge for both of them for two times, and a full charge for one earbud for the third time.