sorry chaps going colder , only used the worktop as it was clean and it has no distractions in what it is , come on chaps must try harder, Darren was partley right, the end has a pin inside that expands the end , it has a rubber "O" ring to close it again , (Hint I am not very mobile)..
also most of us handle the items it was made for each day, even the Luddites.. ( Capt Ludds men)
Peter