The 3rd generation powerprobe includes a number of changes for additional flexibility.  In short, it is a vehicle powered DVM with both a 20 foot cable and an additional 20 foot extension giving you a 40 foot working range around either the battery terminals or cigarette lighter outlet, both clips and a plug are included in the kit.With the series 3 units they use a hard gold plated banana jack to hold the removable probe or cables to extend your reach.  If you purchase the accessory kit, it includes piercing probes that self center on a conductor, pierce the insulation, and attach to the jack allowing you to tap a wire at any point to locate intermittant problems.While the DVM is backlit all the time, it also has 2 bright white LEDs facing forward to aid in finding and probing terminals in dark places.  The actual probe is hardgold plated with a sharp tip and removable at the banana jack.  Another identical probe is included with a screw-in female banana jack in the accessories kit to retrofit the powerprobe I and II units to accept external cables and probes.If you need to excite a circuit with a connection to battery ground or to battery positive, the switch allows a momentary connection to bridge the probe tip to either voltage which is useful in testing relay driven circuits, indicator lights, and other small current loads.  The prope voltage is always displayed during testing on the meter. The voltage/ground switch is circuit breaker protected in case you accidentally drive 12 volts into a chassis ground.  Additionally, since the switch takes abuse it is easily replaced if it fails with just a screwdriver.Combined with the testlead set, the powerprobe 3 greatly simplifies testing of vehicular wire and big rigs up to a single trailer.  The DVM has 5 selectable modes of operation designed for different problems.  Reading the manual is important to get the full value from this meter.Although the price is a little high, the design and construction quality are excellent.  Enough wire is provided to check running lights on trailers or to look for blown fuses.  All of the wiring is exceptionally flexible and heavily insulated with top quality connectors.  Both the tester and accessories come in hard plastic cases that can be stowed in a service box.Not mentioned in specifications is that although the probe runs from 12-24 VDC, the meter can be used to measure voltages up to 80VDC.