一種圓柱形裝置,包含三個或更多個長方形球迴路,並配有一個保持器以引導球沿正確的路徑移動,專門設計用於滑動直線運動軸,以最大限度地減少摩擦和磨損。
0.310 inches nominal overall length, unable to decode material, bearing,radial ball part name assigned by controlling agency, winch,hand operated end item identification, 1.625 inches nominal overall outside diameter