An indication rod or viewing window is set Ascend and descend stemwith the valve to whow the open-close condition, Revolve stem with the valve Use a sealed gear-driving open-close indicating mechansim.

• 升降杆阀门设有指示杆或观察窗以表示阀门的启闭情况,旋转杆阀门采用封闭齿轮转动启闭指示机构。