Mount Shoe Guide No. 141.08' (43 m) ISO100 at 105 mm position Exposure Control E-TTL / E-TTL II Angle of Coverage 84° - 23.3° Wide-Angle Adapter: 114° Vari-Power 1/1 - 1/64 Bounce Head 0° to +90° Swivel Head 330° Coverage 14 mm - 105 mm (Full frame) Distance Range 2.30 to 77.43' (0.7 to 23.6 m) at f/1.4 Zoom Head Full frame: 24 mm - 105 mm Off Camera Terminal None Recycle Time Approximately 0.1 - 3.5 seconds Flash Duration Not Specified By Manufacturer Flash-ready Indicator Yes Compensation -3 EV to +3 EV (in 1/3 and 1/2 EV steps) Wireless Operation Method: RF Distance: Up to 98.43' / 30 m Method: Optical pulse Distance: Up to 49.21' / 15 m Wireless Communication Channels 15 Channels Wireless Groups 5 Groups Power Source 4x AA Alkaline, Rechargeable NiMH Batteries Dimensions (WxHxD) 2.8 x 4.5 x 3.9" / 70.5 x 113.8 x 98.2 mm Weight 10.41 oz / 295 g