F 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. F Philips 279C9, 27", 3840 x 2160 pixels Philips 279C9. Display diagonal: 27", Display resolution: 3840 x 2160 pixels, Native aspect ratio: 16:9 https://www.itpro.co.uk/hardware/monitors/361826/philips-moda-27-4k-review-moda-moda-burning-bright The Iiyama ProLite XU2792UHSU-B1 aptly demonstrated that there's no need to spend almost £500 to buy a 27in 4K monitor, so the question you may be asking yourself is what makes the Philips Moda 27 worth its rather weighty pricetag, compared to cheaper alt... https://www.techradar.com/reviews/philips-279c9-monitor Precision productivity. That's the Philips 279C9's core proposition. It's a 27-inch 4K monitor that not only offers precise image quality thanks to its 4K native resolution and IPS panel. It also offers sharp styling and a feature set finely tuned for eas... Gorgeous 4K IPS panel, USB-C with charging and hub, Sleek slim-bezel design Not a true HDR monitor, Limited color coverage The Philips 279C9 is neither a true HDR monitor, nor does it offer the kind of color coverage that demanding content creators will desire. But that's just fine, given the price point and this screen's remit.Think of it instead as a precision productivity...