HEX-A-JUST Allows for Infinite Valve Timing Adjustability of +/-6 Degrees to Tune for Maximum Engine Performance Output. One Piece Camshaft Sprocket Design Featuring a Billet Eccentric Camshaft Dowel Bushing. Both Billet Steel Sprockets are Heat Treated for Durability. TRUE Double Roller 0.250" Roller Diameter Chain for Reduced Friction. Sets Hand-Matched to Qualify the Correct Center Distance and Minimize Runout. 0.005" and 0.010" Reduced Length Chains Available, to Order Add -5 or -10 to the End of this Part Number