一種通常呈圓形的剛性部件,用於容納軸承。它用於定位軸承,但不會包裹軸承或限制軸承的運動。
0.3650 inches minimum and 0.3850 inches maximum overall width, 2.0020 inches minimum and 2.0060 inches maximum outside diameter, 1.2500 inches nominal bore diameter, c-17a,aircraft end item identification, rubber butadiene-acrylonitrile class nbr retainer material