Guide Number : 190 (at ISO 100, feet) / 58 (meters); flash head at 105mm zoom setting
Number of Flashes : Approx. 100 to 700, with fresh AA-size alkaline batteries
Recycling Time : Approx. 0.1 to 6 seconds, with fresh AA-size alkaline batteries
Flash Range : (At ISO 100, with 50mm f/1.4 lens at f/1.4) - Approx. 1.6 to 98.4 feet / 0.5 to 30m
AF Assist Beam : Built-in; covers all focus points in EOS cameras with 1, 3, 5, 7, 9, or 45 AF points; Distance range - 2 to 32.8 feet (0.6 to 10m) at center; 2 to 16.4 feet (0.6 to 5m) at periphery
Custom Functions : Fourteen Speedlite Custom Functions built-in; set on Speedlite's LCD panel
Power Source : Four AA-size batteries - alkaline, lithium, or rechargeable Ni-MH usable
External Power Source : External power supply - compatible with Dust- and water- Resistant External Power Pack, Canon battery pack CP-E3 and Transistor Pack E