Dynalite MK4-1222 Kit with MP400 400W/s RoadMax Power Pack, Two MH2050 Roadmax Flash Head, Two Umbrella and Stands Fires from your PocketWizard radio slave transmitter, the included sync cord, or from the built-in optical slave (from other flashes) Varies only approx. 0.1 stop from shot to shot Color temperature varies 80deg.K over the exposure range - not visible to the human eye Compact and lightweight Very precise power controls provide 6 stop power range