實心或空心結構的圓柱體,為滾子軸承提供滾動元件。
steel comp e52100 overall material, 0.1248 inches minimum and 0.1250 inches maximum overall length, 0.1248 inches minimum and 0.1250 inches maximum rolling element diameter, sae-j770 assn std single material response overall material document and classification, needle roller, ball ends style designator