The fine pore, silk-like to the touch, Grand Prix Cover is perfect for fine particle sand conditions. It has elastic around the bottom of the cover that allows it to sit perfectly around the air filter, preventing fine particles entering the filter and in turn your engine. The Cover will act as an additional layer of protection and extend service time between filter cleaning. GRAND PRIX COVER - (STANDARD AIRBOX) FANTIC XXF450 24-25 YAMAHA YZ250F 24-25 YZ450F 23-25 YZ250FX 25- YZ450FX 24-25 WR250F 25- WR450F 24-25