amp probe question



I am purchasing a Greenlee CMA-60 AC/DC Clamp-on Current Adapter and
would like to extend the wire leads to my millivolt meter by 25
meters, think this would give me inaccurate readings?
I would also like to know if anyone has an ideas on how I could have
an audio beep to let me know when anything above zero millivolts is
being read.
Thanks.
.