drag link ball seat 拉杆球座
machining steel ball seat 钢球座加工
shearout ball seat sub 剪切球座接头
ball and seat 碎石; 道碴
ball and seat valve 球形止回阀
ball check seat 球形阀座
ball resolver seat 球形分解器座
ball resolver valve seat 球形分解器阀座
ball valve seat 球阀座
ball-and-dish seat type valve 球及球座型阀
ball-and-seat 单流阀
centering ball and seat 中心球和座
leather ball & imitation leather ball 皮球及仿皮球
leather ball & synthetic leather ball 皮球及合成革球
valve seat body seat 阀座
2-dimensional ball-bar 二维球杆仪
3-way ball valve 三通球阀
40mm ball 大球
a ball of fortune 受命运摆布的人