This item is a RS-232 breakout box with some sophisticated functions.
I think it is new old stock, no signs of use.
It is a CPU controlled unit that also acts as an error detector.
It runs from a plug-pack, but it also contained a 9V PP9 style rechargeable battery, that will need replacing as it has lost capacity after charging.
It comes with the manual, carry case and the original power adapter.
According to the manual it has 9 applications involving serial links. It is described as an Async/Sync bit rate tester and RS-232-C breakout box, battery operated , microprocessor based, pocket sized test set that is capable of performing error rate testing at a synchronous data rate of up to 38.4 kbps.
It also come with a very nice carry case. This sort of tool can be very helpful working with RS-232 serial links.
PLEASE NOTE:
For some reason I have not being receiving Ebay automated messages that an item has sold (I have no idea why yet) So if you do buy it, please contact me to advise that you have.