可使用性

The allergic and dark skin of sycosis also can have peace of mind the usage.

过敏及暗肤也可安心使用。

4 All removable internals shall be checked by suitable methods to ensure their insertability and removability through the manhole.

所有可拆除内件均需使用适当的方法进行检查以确其通过人孔的可嵌入及可拆除。