RS232 Serial Interface Breakout Box(BOB) Tester - supplied with 25 way M to F patch ribbon cable and a selection of pin to pin patch leads .

Allows 25 way(M & F) cable testing with pin to pin patching, individual signal isolation switches allows signal patching, and Red/Green led indications according to signal polarity for each of the 25 signal connections..

All in all,  a very useful diagnostic tool to help locate signal issues and incorrect cable connections between DCE and DTE RS232 interfaces.