| Type | Nominal Size | Opening Model | Storm Cover | Application |
| Heavy Type | ∅200mm | Right & Left Opening, Joint hinged | Hook type,Pawl type | Water tight and gas tight requirements,above full load water line ,below freeboard. |
| ∅250mm | ||||
| ∅300mm | ||||
| ∅350mm | ||||
| ∅400mm | ||||
| Medium Type & Light Type | ∅200mm | Above freeboard,first deck. | ||
| ∅250mm | ||||
| ∅300mm | ||||
| ∅350mm | Right & Left Opening | - | Above freeboard for passenger ships. | |
| ∅400mm | ||||
| ∅450mm |






