While a standard coil is great for finding large objects that are deeply buried, the 4-inch coil has a narrower field fo detection - enabling your detector to separate objects more efficiently.
The 4-inch coil's shallower detection area makes it ideal for prospecting in difficult, high metal areas since it allows you to more easily discriminate valuable objects from refuse.
In addition to allowing the precise pinpointing of objects, a smaller coil lets you probe tight spots such as corners and crecives.
