套秒的電話號碼，以環數。
Useful when you have to open a cacello electric with a single ring etc ...
Statistically it is seen that 7/2 correspond to the first ring.
套秒的電話號碼，以環數。
Useful when you have to open a cacello electric with a single ring etc ...
Statistically it is seen that 7/2 correspond to the first ring.