Anyone got one? Which way round does it fit?

I got this ages ago and its been in the shed. Im sure it had some instructions when i got it but can i find them?

Ta folks.

Matt,
just try blowing through it.
That will indicate which way round it goes, since air needs to be expelled from the engine and not be drawn back in...

ken

I went for the blow through it approach to work it out.

You can also unscrew the two halves and see the valve for more of a hint.

Oh crikey,

I must be loosing it, why the heck didnt i think if blowing through it.

Thanks Ken and terpineol.

I must think before posting in future.