NOTE: IF YOU BUY A FACTORY SEALED unit, you risk finding a corroded battery because every savvy owner should have known that units need their preinstalled battery removed if long-term storage is planned.

This item was gently opened at the top many years ago to *remove* the pre-installed 9-volt battery -- and that is all that was done.  Again, IF YOU BUY A SEALED unit, you risk finding a corroded battery because every savvy owner should have known that units need their preinstalled battery removed if long-term storage is planned.

Also note: You can change your 'version' of this item by merely downloading a different version's software from the internet (easily found by searching). The hardware is the same for every 'version' advertised by the manufacturer.