what's the biggest value adwords voucher?

i'm a newbie in adwords, frankly i never used adwords, and before starting up i would like to know what's the biggest value voucher

as far as know the highest value voucher is the 200$ one

but for instance if i use a 200pound voucher will it count as 400$ ?(1 pound is almost equal with 2$) or is it available just for UK users?

thanks a lot,
Tom

 

well i never got a voucher yet if u like to give me 1 free plz PM it to me

 

Your voucher must be the same currency as the currency you are paying for your clicks.

Let's say if you are paying in US Dollars for your clicks, then you have to use dollar vouchers.

I am not 100% with this, maybe someone knows better