Technical Smithy's mounting direction

To those who have used Smithy's mufflers, I've a doubt concerning the direction of the mounting !
There is an arrow on the muffler and engraved "inlet", but does it indicate the direction of the gas (in that case, gas must enter by the other side, not shown on my pic) or the side where gas must enter ? (please, see the pic)
Thanks !

 

If you look inside the mufflers there are louvers, opening of the louvers are ment to be facing backend of vehicle .
Idea of the lovers are when gas flows over the louvers it creates a kind of backdraft

 

Im not sure if it makes any difference if you mount them "backwards" probably it restricts the flow more if the louver opening are facing the engine

 

Any muffler that I ever installed, when marked, the arrow pointed to the inlet side. Not the direction of flow.

 

If there is only an arrow it is the flow direction.
When A - B is used, gas flows from A (inlet) to B (outlet).
When there is the word 'inlet' and an arrow, the arrow is pointing at the inlet.
The end you can see in your picture is the inlet. The flare to allow the pipe to fit inside also looks right for the inlet.

 

I tend to agree with the louvered info, but have to say inlet is where the exhaust enters.
Ie you don’t exit the enter door.

 

Thanks to all, you confirmed my opinion ... an arrow plus the word inlet means this side is the inlet !