Please take a look at this Youtube DIY Video that teach you how to use this step-down module to DIY Building a TRUE 4k home cinema projector (it’s awesome)
it's very useful and funny if you DIY by yourself.(Video from Web Celebrity “DIY Perks” at Youtube website)
DIY 4K Home Cinema Projector: https://www.youtube.com/watch?v=YfvTjQ9MCwY
The cost performance of our COB LED is better than YUJI COB LED. YUJI COB is too expensive
What is CRI:
Color Rendering Index, it describes how a light source makes the color of an object appear to human eyes,and how well subtle variations in color shades are revealed. The CRI is a scale from 0 to 100 percent indicating how accurate a "given" light source is at rendering color when compared to a "reference" light source.
The higher the CRI, the better the color rendering ability. Light sources with a CRI of 80 to 90 are considered good at color rendering. Light sources with a CRI of 90 or higher are excellent at color rendering and should be used for tasks requiring the most accurate color discrimination.
Product parameters of 300W COB LED Warm White:
Brand of LED Chip: CITIZEN
Color Temperature: 3200K
Voltage (V): DC47.8-56.2 V
Current (mA): 5750mA
Luminous Flux (LM): 30000-35000 LM
CRI Ra 97
Material: Copper Brackets
Working Temperature: -30-60℃
Note: It will work more than 30000 hours if the working temperature is less than 60 Degree Celsius. So, they need to work wih heatsinks or Thermal Silica otherwise the light will die due to too much heat. Please see this youtube Video at listing page.
Package Included: 1 x 300W COB LED Warm White