Maybe you should, but perhaps you were trying to make the point that the OP had the same misunderstanding' about the meaning of 'low voltage' as do the vast majority of the general populationMaybe, I should have asked why he has squandered £6 on a meter that was not capable of measuring "mains" voltages.
As for the meter, I can't recall having seen a cheap multimeter which is not capable of measuring "mains voltage", and I've certainly never owned a multimeter which couldn't!
Kind Regards, John