Beehive Valve Spring Kit designed as drop-in performance valve train upgrades. Beehive valve springs deliver a host of well-documented benefits over conventional cylindrical valve springs. Increased rpm capability with no rocker box clearance problems. Designed to work with the limited valve spring installed height of the Harley-Davidson V-Twin engine, small spring pocket and high-lift cams. Kit PART #0926-2899 features industry-first lightweight tool steel retainers; 30%+ lighter with greater strength and durability than conventional chromoly steel retainers. Made in the U.S.A.