I don't remember much about it. I found this years ago and it's been in my treasure box with some of the many Barber dimes, Indian heads, etc., I found while detecting back in the late 60's to mid 80's.
I think I found it with my Fisher 1260-X while hunting an old park in Michigan. Most of the finds in that park were almost exactly 2 3/4 inches deep. I discovered this when I bought one of the Coin Computer detectors. It had a depth gage on it.
By-the-way, what ever happened to that company? It think they called the company "Technetics" and their detectors were "Coin Computers." It seems to me it was formed by a group of people who left Whites? Maybe I've got it wrong.
Those were pretty good machines. The design made them a little hard on the wrist and arm but they had pretty good depth.