sight window

• 观察窗,观察孔

sight window的用法和样例：

例句

1. There is an observation window on the hatches available for watching during operation.
   检修口上设有观察窗，在搅拌过程中方便观察。
2. The outer door is a polyurethane foamy one with a glazing unit observation window, for better perspectivity and heat preservation.
   外门为聚氨脂发泡门，中空玻璃观察窗，透视性好，保温性能好。