*High Speed Sync* TRIOPO TR-988 Professional Speedlite TTL Camera Flash for Digital SLR Cameras from Canon and Nikon Details Insulated gate bipolar transistor (IGBT Guide Number: 56; ISO 100, 180mm) circuit design Manual 18-180mm flash coverage, automated zoom, swinging, and tilting flash head (bounce flash) Flash Mode: on/off camera, TTL, M, Multi, FEB, Slave, S1, S2 HSS capability (up to 1/8000s) Light rotation: -7° to 90° vertically and 0° to 180° horizontally Wireless induction flash lighting is the wireless trigger. With an AA alkaline cell, the wireless triggering distance is 20-30m (65-98 feet) indoors and 10-15m (32-49 feet) outdoors. The lighting times are 100-1500 times. Temperature of color: 5600K Flash Duration: 1/200-1/20000 seconds Flash Control: 8-step (1/128-1/1) power control 22 fine-tuning stalls in total, with a step length of 0.3EV Unit and Slave Group: 4 Channels (1, 2, 3, 4); 3 Groups (A, B, C) Interface on the edge: Hot