This inexpensive and very portable test set can handle all manner of diodes and transistors, detecting type and pinouts on a colour screen. It can also accurately measure resistors and capacitors and reports ESR. The items can be inserted anywhere in the ZIF socket provided. It would have earned a fifth star if the ZIF socket could be mounted in a more stable fashion, but this is overcome with careful handling. Highly recommended - a very useful item for identifying and measuring all the usual single components.