Weather resistant louvres GW have a special design with 1 row of fixed Z-shaped blades, 45⁰ inclined, parallel to the 1st dimension, which offers protection against rain. They are suitable for use in air-conditioning and ventilation systems and outdoor wall or air-duct installation, for supplying fresh air or indoor air exhaust.
Weather louvres GW can be manufactured from anodized aluminium, aluminium painted in RAL color, from galvanized or stainless steel and copper:

GW... : Blades & frame from anodized aluminium or aluminium painted in RAL color.
GW... | C : Blades & frame from copper.
GW... | GL : Blades & frame from galvanized steel.
GW... | I : Blades & frame from stainless steel.