JOKER DRIVER is known to be the best manufacturer producing the highest quality of darts. What makes the highest quality is its all domestic-producing darts methods that enable the weight difference of within 0.03g and the length difference of within ±0.01mm among 3 dart sets. You can feel the difference of suitability of a dart barrel to your fingers that special minute polishing process makes possible. Its Zero series and Scuderia series apply this method to each model. ※5 year manufacture warranty applicable.