Compatible Cameras: for Canon DSLR Camera(TTL autoflash)
• Guide No. (1/1 output  200mm): 60 (m ISO 100) 190 (feet ISO 100)
• Flash Duration: 1/300 to 1/20000 Second

Exposure Control:
• Exposure Control System: TTL and Manual Flash
• Flash Exposure Compensation(FEC): Manual. FEB: ±3 stops in 1/3 stop increments (Manual FEC Can be Combined.)
• High-Speed Sync(up to 1/8000 Seconds), First-Curtain Sync, and Second-curtain Sync.
• Multi Flash: Provided (up to 90 times, 100Hz)

Wireless Flash (Optical Transmission and 2.4G Transmission):
• Wireless Flash Function: Master, Slave, Off
• Controllable Slave Groups - 2.4G: 3(A, B and C) Optical: 2(A and B)
• Transmission Range - 2.4G wireless : 100m , Optical: Indoors:  15 m
• Channels - 2.4G: 32(1-32), Optical: 4(1, 2, 3 and 4)
• Slave-Ready Indicator: Two Red Indicators Blink

Godox TT685 also have their own 2.4GHz radio transceiver unit built inside, providing full TTL and HSS enabled Radio Master and Slave modes, with a range of up to approximately 100 meters.
An External Battery Port is provided at the front of the flash, for connecting battery packs. TT685C features a larger Dot Matrix LCD display with on screen menu options. As well as fully back-lit function buttons, including extra Link and Mode buttons.
The Godox X1 TTL transceivers can also be used as a Master / Transmitter unit mounted on the camera to control the TT685’s off camera.