I tried the 9v. battery to get AAAA just for fun to see if I could feed my Slylus with them. I only tried one 9v. battery, so the test was not extensive, but the results were not as good as I had hoped.
First, the individual elements inside the 9v. battery have been pressed to fit into the 9v. case. they tend to be out of round and bulged in one or more places. Several of the elements would not fit into the barrel of the Stylus, or would fit only with undue force. This would make the battery difficult of impossible to remove later.
The second problem is that the elements from a 9v. battery are ever so slightly shorter than a AAAA battery. Replacing the AAAAs in the Stylus with the only three 9v. elements that would fit easily into the barrel, the overall difference in length made it impossible to turn the light on as the switch could not make contact.
I was eventually able to get the light to work by removing one of the contact snaps from the top of the 9v. battery and inserting it between the first and second elements, and removing a foil strip used to connect the elements in the 9v. battery and installing it between the second and third element.
I removed the 9v. elements, replaced the AAAAs and have not pursued the issue further.
Mike
