Hi Sinner

The code below would be one way to do it, though it will all depend on
if your numbers in column C being the same length. Also i added an
apostrophe to the start of the value in column J to stop it from
changing to show "1" and dropping the leading 00. This can be removed
from the code by deleting "'" & from the code.

Paste this code into the module for the sheet you want the code to
run.

Private Sub Worksheet_Change(ByVal Target As Range)

If Target.Column = 3 Then

Cells(Target.Row, 10).Value = "'" & Mid(Target.Value, 7, 3)

End If

End Sub

Hope this helps

Steve