AODELAN Q2 300TTL is a flash system powered by a lithium Battery Pack and the Unit can control  two Flash Heads at the same time. Supports TTL and High-Speed Sync flash, allowing you to  quickly obtain accurate exposure and easily control the light. Also, TTL and manual modes can be  used in combination, Q2 300TTL enables you to keep the TTL exposure parameters when you  switch the flash trigger to Manual mode, to provide a good starting point for manual metering. Q2  300TTL also provides a Freeze mode, which freezes the subject on the picture with extremely fast  flash durations.  The battery pack