Mobile phone cancel outer

How do you call the tool that prevent others from making phone calls
when switched on?

allahgodalmighty@yahoo.co.uk brought next idea :
> How do you call the tool that prevent others from making phone calls
> when switched on?

The off button?

Call Barring?

On 7 Nov, 19:05, Jono <notha...@blueyonder.invalid> wrote:
> allahgodalmig...@yahoo.co.uk brought next idea :
>
> > How do you call the tool that prevent others from making phone calls
> > when switched on?
>
> The off button?
>
> Call Barring?

Mobile Phone Jammers. Allahgodalmighty googled and found the answer.