Diffuser; In fact, it is also a whole vent only requires to "spread out the air flow", which becomes a "diffuser". The blade of a diffuser is arranged symmetrically outside obliquely, mainly to spread the flow around. Usually only made a layer of leaf, only used for air vents.
Louver vents; Also divides the air outlet and the return air outlet, has the single-layer louver tuyere and the double-layer louver tuyere two kinds. Those with and without filters. The outer louver of the air outlet can be adjusted to point the air flow in one direction. Because the tuyere is like a Venetian blind, it is called a louver.
There are two kinds of diffuser and louver with regulating valve and without regulating valve.
Materials are iron (fire system), aluminum, wood, stainless steel, plastic, glass steel.