Goods, articles and parts of ship's appliances: rectangular ventilating water-gas-tight covers

Purpose: ventilation rectangular covers used in ventilation and air conditioning systems of ships, vessels and watercraft.
Type II - steel and light alloy covers with hinge arrangement on the long side.
Version: 1 - with louvres (blades parallel to the long side);
2- with louvres (blades parallel to the short side).
The nominal passage 125-500mm, thickness of the coamings 3mm.
Method of fastening: welding.
Climatic version OM, category I according to GOST 15150: ambient temperature from minus 40? to plus 45?.
Main material: aluminium alloy