Extra button on my new GP32???

[Oliboli]

I have just got my new GP32 through the post this morning and I have noticed that there is an extra button on the back which I can't see in any of the promotional photos, specifications or manuals. It is located about 5mm to the right of the SMC slot on the back of the GP32. It is a 2 position push button. The head of the button is about 4mmx4mm. Can anyone tell me what this is?

(Forgive me if I am being dumb and this is really obvious, I just can't find any reference to it anywhere....)

 

[Azure]

It's the button for the front light...

 

[Oliboli]

Ahhhhh..... Now everything is clear! Literaly.
Cheers for that. I havent got any batteries so I couldn't test it out.....