Flash Control: With a guide number of 38 (ISO 100), it supports manual optical control (M) and S1/S2. In M mode, the flash output can be easily adjusted from 1/1 to 1/128 in 1/8-stop increments. Note: Does not support TTL, HSS and camera menu settings.
Power Management: Slide the switch to the on position, the flash will start charging (charging indicator is dim)
For a flash test, press the test button; after use, move the ON/OFF switch to the OFF position to turn it off
Red light indicator flashes every second: indicates battery is low; flash has 8 power adjustment steps indicating 8 LED flashes for different levels
Widely Compatible: With the single point of contact hot shoe, it is compatible with Canon Nikon Panasonic Olympus Pentax cameras with standard hot shoe and also with Sony MI hot shoe, such as a9 a7 a7II a7III a7R III a7RII a7SII a6000 a6300 a6500 (not compatible with EOS Rebel SL3/250D Rebel T7/1500D 2000D Rebel T100/3000D 4000D).