Huion 23.62 Inches Light Box with Ball Stand and Tracing Paper The Whole Light Pad dimension including Black Frame is 19*14 Inches With Diagonal of 23.62 Inches. The Illuminated is 17.3*12.6 Inches With Diagonal of 21.46 Inches Adjustable Brightness --- simply press the touch switch for several second untill the brigness you want (From Bright to Dark) Memory Feature --- smart memory the brightness of your last use Touch Switch Design --- you only need to touch the pad to turn on / off your light box Suitable for 24hour lighting, Long life span 50,000 hours