Samsung NX500 Dual Macro LED Ring Light/Flash (Includes Necessary Adapters/Rings for Mounting On All Samsung Lenses) Flash Guide Number: 15 Feet Effective Distance: 1.96 Inches- 5 Feet Color Temperature: 3000-15000K Exposure Time: 1/100s Power: 4 x AA batteries or Ni-MH Rechargeables, Weight: Approx. 7 ounces