Not sure, but maybe the one that came with the Pro-2035/42?
Are they still available even?

"HK" wrote in message
news
Hello, the screw-in whip antenna (pn 10538270) for the Pro-2006 is no
longer
available from Radio Shack. Anyone have a source for the same antenna or
an
exact replacement (clone)?
Thanks in Advance,
HK