The 30.7 cm (12.1 inch) [247 x 186 mm] is the screen size of a specific device that our website sells a range of screen protectors for. It is important to know the exact screen size of your device in order to choose the correct screen protector that will fit perfectly and provide optimal protection. Our website offers a variety of screen protectors that are specifically designed for this screen size, ensuring that our customers can find the perfect fit for their device and keep their screen safe from scratches, cracks, and other damage.