VBA, remove all characters within a string, except numerical characters and full stops

I'm after a code that would remove all characters within a string that are not numbers (1234567890) and aren't full stops (.)


So lets say I have a string of text "ts [$11.40 USD]" (without quotes) in col F
Then after I would run the macro, it would only leave "11.40"
I'm looking for an easy and efficient code.

I have piece of code below that replaces "]" with blanks "". That is just an example that I would like to replace with something as described above.
Any help is very much appreciated. Any ideas?

Sub simple_test()
For r = 2 To 30

'the line below replaces "]" with blanks e.i. ""
Sheets("Sheet1").Range("G" & r) = Replace(Sheets("Sheet1").Range("G" & r), "]", "")

Next r:
End Sub