Package contents:One (1) professional flash head, power output 400ws (joule) in full Specifications: Guild No. 64 (ISO 100) Circle flash tube: Color temperature: 5500K, exchangeable, made by PerkinElmer (Heimann). Ave. flash bulb life: over 8000 flashing. Flash power setting: 1/16 to 1/1 full step less variable with separate switch. Recycling time: 0.5~3.7 sec. Flash Triggering: Photo cell,Sync cord, and Test button Power input: 110 volts, 60 Hz. Modeling light: with on/off switch. Bulb included, E27 socket, up to 100 watt. Sync.Voltage: DC 12 v. Cooling fan: Built-in. Audio signal on/off switch. Beep when ready for flash. Weight: 3.45kg. Power cord, sync cord and an extra fuse are included.