The 54.9 cm (21.6 inch) [464 x 290 mm] is the screen size of a specific device that our website sells a range of screen protectors for. This measurement is important for customers to know so they can select the correct size screen protector for their device. Our website offers a variety of screen protectors that are designed to fit this specific screen size, ensuring that customers can protect their device from scratches, cracks, and other damage. By providing screen protectors that are tailored to this specific screen size, we aim to provide our customers with the best possible protection for their device.