Review on Amprobe PM55A Multimeter Non Contact Detection by Joe Lara

Amprobe PM51A Pocket DMM Pros: Very small and thin, fits in a shirt pocket; with fixed exits. The smart, rotating black switch sits almost flush with the body, but rotates easily to select resistance, dc or ac volts, beeping continuity, capacitance, or frequency. Big numbers make it easier to read. Press the hold button and the screen will lock - disconnect the cables and read the meter reading. Cons: While it worked well for a few years with intermittent use, the accuracy eventually declined. For example, it shows 45.4 volts across a 16 volt DC transformer. A new, higher quality multimeter showed the transformer at 18.6 volts, which is about as expected. Extremely incorrect readings rendered the device unusable, so it was disposed of.