E means that the product is rated in its category in terms of energy efficiency. The Energy Labeling system is based on EU Regulation 2017/1369/EU. E AOC 24B3CA3/75, 60.5 cm (23.8"), 1920 x 1080 pixels, 4 ms, Black AOC 24B3CA3/75. Display diagonal: 60.5 cm (23.8"), Display resolution: 1920 x 1080 pixels, Response time: 4 ms, Native aspect ratio: 16:9, Viewing angle, horizontal: 178°, Viewing angle, vertical: 178°. Built-in speaker(s). Built-in USB hub. VESA mounting. Product colour: Black