This kit is designed for quality digital studio photography both in the light that it produces and in the workmanship of the materials. The light heads feature ceramic sockets for long life, bayonating reflectors for secure fit and a shape that is designed to produce even light with no hot spots or concentric circles. The CSA line cord has a heavy duty on/off switch to ensure years of reliable use. The white umbrellas have a black backing to maximize the light. The 8" reflectors are sized to allow the maximum amount of light to reflect back to the subject. Additionally, the socket of the reflector can be adjusted allowing the light to be "focused" changing the edge of the light from soft to hard. Also, this adjustment allows the umbrella to be filled without unnecessary spillover resulting in lost of light.