Apple weds high-res 4K visuals into its sleek 21.5" iMac with Retina 4K Display (Early 2019). In addition to its 4096 x 2304 screen resolution, its display offers 1 billion colors at 500 nits of brightness. The Retina 4K display also features the wider P3 color gamut, which provides a larger color space by utilizing red-green phosphor LEDs that uniformly represent red, green, and blue. And with more available colors, images will appear more vivid and reveal greater detail, with more balance and precision.