YK-B144T, microscope led ring light Specification: Outer diameter : 98mm Inner diameter: 61mm Wattage:4.5W Input voltage:90V-264V Output voltage:DC12V Brightness adjust:0-100% Working distance:50-250mm Quantity of LED:64PCS Brightness:16000Lux at height of 100mm Color of light:6400K Warranty:1year