内开式带斜边椭圆人孔 Ellipe manhole cover
卫生级方形人孔盖Sanitary square manhole cover
卫生级人孔盖YAC型manhole cover (model YAC)
卫生级椭圆形人孔盖Sanitary manhole cover (model YAB)
卫生级压力圆形人孔Sanitary pressure manhole cover with glass
卫生级圆人孔Sanitary manhole cover
卫生级圆人孔Sanitary manhole manhole cover
无压力圆形人孔 1No pressure round manhole cover 1
无压力圆形人孔2 No pressure round manhole cover 2
圆形人孔带玻璃 manhole cover with sight glass
