DRT Cylinder Head Dome Insert ONLY YAMAHA YZ250(X) 1999+DRT Cylinder Head Dome Insert Yamaha YZ250(X) 1999+ DRT cylinder heads are the cutting edge of cylinder head design, offering optimized performance for every riding style. Proudly designed and manufactured in the United States! Benefits compared to stock: Optimized performance: more power where you need it, when you need it Choose between 3 dome insert options. Order one, two, or all 3 to unlock full control over the feel of your engine. Each dome