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The blank employs aluminum alloy with high inflexibility and strength, and small rotational inertia, decreasing oil consumption. Its working face is either inlaying structure adopting powder metallurgy with good shock resistance and durability, forming a friction pair by matching with cam, or roller structure employing needle roller bearing, changing sliding friction into rolling friction, decreasing abrasion. The hydraulic lifter is used to replace the adjusting screw and is integrated into rocker arm, making structure more compact, in this way, the force direction applied by push rod is changed and the valve lash is automatically cleared, decreasing noise.