parallel test bar平行测试杆
parallel rectangular bar reticle平行矩形带调制盘
parallel l bar双杠
parallel slipping bar composite support并联顶梁滑移支架
dipping on parallel bar双杠上撑
uneven parallel bar高低杠
Two Parallel Bar Structure两个平行酒吧结构
parallel bar dip负重臂屈伸;双杠臂屈伸
standards for parallel bar双杠支柱