Upper-roll fixed, the two rollers under a fixed turn around the center arc movement take-off and landing, under two separate movements can roll up or down with.

上辊固定，两下辊围绕一固定回转中心做弧线升降运动，两下辊可单独升降或同升同降。

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Haas hit an even better shot, landing it about 15 feet short of the hole and watching it roll into the cup.

NPR: Haas Shoots 64 To Take Lead At Riviera