I love mine, it came as the standard coil on my F70 and I used it for many weeks before I got any DD's then after using DD's for months I switched back just for a change and I was a little shocked...the tones on most targets sounded different...clearer, tighter, sweeter is as close to a description as I can get.
Over precious metal like silver or gold in either jewelry or coin form, It...Just...Sings!
Hard to explain the difference but listen to targets using both types of coils for a few hundred hours and you can tell.
Works great on hated pop tops and can deal with trash and iron infested sites easier than you might think.
The elliptical concentric has a shape that to me mimics a DD, it has a distinct sweet spot and pinpoints like a laser.
As far as depth in good soil my concentric lacked about 2" compared to the 11"DD in getting an accurate ID, (12" vs 10"), in my bad soil where I hunt now it's a wash.
Neither gets super deep here, it is more about dealing with masking and both kinds do well for me in that areana.
I am in Bama, red clay, natural occuring iron everywhere, massive iron from knocked down buildings and neighborhoods, trash galore and more.
3 bars minimum most of the time and GB numbers up through the 70's and even into the 80's, sometimes.
For years those that bought an F70 with this concentric coil were told to sell it and get the 11"DD instead and many did some without ever using it.
In my mind this was a mistake....especially if you are a jewelry hunter like me.
Like my snipers a good concentric is a beloved accessory in my arsenal.
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