Clearview brand screens use existing hardware.....for the R3T anyway. Other brands may include their own fixings, especially if their screen is to fit a bike not originally equipped with a factory screen. In most all cases every brand which lists a screen to fit your bike, will also say whether they want you to get their mounting kit or whether you may use factory fixings. With many brands, the shield itself is somewhat universal and you get whichever mounting kit works for your bike. Any screen which can use the factory fixing kit, is going to fit so much better I do think. But many brands which have their own have well engineered kits, and if you take the time to do it properly they will do fine.