An electronic probe or pinpointer is a hand-held detector that is quite effective in locating coins and small artifacts inside dirt plugs, dug holes and in piles of dirt and sand displaced from the dug holes during target recovery.
Using the pinpointer cuts the target recovery time down at least in half, and even more if used by an experienced detectorist. And last but not least, the pinpointer helps a detectorist avoid any accidental scratching or breaking a valuable target with a digging tool.
Nowadays, when the time efficiency in the field makes a huge difference between losers and winners, the pinpointer is a "must-have" if you aim at being the latter. If you purchase an additional search coil before acquiring the pinpointer, you make a mistake. In any serious treasure hunter's arsenal, the up-to-date pinpointer undoubtedly should be #4 after a metal detector (#1), headphones (#2) and a shovel (#3).
In my arsenal, I have two pinpointers: Garrett Pro-Pointer (described on next page) is for coin shooting, and Vibra Probe 580 (described on page 5 - "Vibra Probe 580") is for cache and relic hunting in highly mineralized ground. Each pinpointer has its advantages and disadvantages over another but serves the purpose to my advantage when used under certain metal detecting conditions it is designed for.
I did not use any pinpointers or electronic probes during my first five years of metal detecting. That was how I trained my eyes to spot dug targets in dirt even though most of them, except gold, appeared to be the same color as the surrounding loam.
I started using the pinpointer when I got into detecting the tiny hammered coins which, if plastered with dirt, are impossible to distinguish from surrounding nubs of dirt, especially in dim light conditions. After I discovered the pinpointer's potential, I only regretted that I did not start using it much earlier and save more time for actual metal detecting.
If you metal detect on manicured lawns, the pinpointer should be used before digging. When a target is lying within a couple inches of the surface, the pinpointer allows you to determine the target's precise location, so you dig up a small dirt plug.
Using the pinpointer, you can also outline the object to see its size in order to avoid excessive digging; thus, causing minimal damage to the lawn.