whether or not it will 'work' for you and what you want to accomplish is another thing.
I've tried the 13" Ultimate and other after-market search coils from different makers on a fair assortment of detector brands and models. As a general rule, I haven't been overly impressed with most of them. Quite often there will be a coil made that isn't offered by a detec6or manufacturer so that might add a little performance, such as the after-market 7" DD made by Detech for White's MX Sport and MX-7. At the time the MX Sport came out, they didn't have a smaller-size search coil to offer until the 7" DD was introduced.
When the MX-7 came out there was a prototype 6½" Concentric in the works, and that was finally announced yesterday with the release of the new Six Shooter Concentric for the MX Sport and MX-7. I am going to have to buy one of these new designed 'flat bottom' coils for my MX-7 arsenal to complement my early-style 'fat body' coil design. These coils work for most of the trashier sites I hunt, and so does the 7" DD Detech, plus it is a handy coil for working in shallow water as it doesn't float. I wish they made the open-frame 9" Concentric for them, but until something better comes along, the stock 950 of the MX-7 will handle most of my searches in open wide-open areas with limited masking trash.
As for a larger-size search coil, the 13" Ultimate coil made things nose-heavy and poorly balanced for me, and for the Coin & Jewelry Hunting as well as working the Relic Hunting sites I favor, there wasn't any real benefit. Actually terrible performance in any moderately or heavily contaminated site. Then, if you are hunting more open areas, with limited trash, and you anticipate desired targets to be a little deeper than average, then maybe the 13" Ultimate coil could be useful.
So, YES it will 'FIT' the excellent MX-7, but it's hard to say if it will 'WORK' for what you anticipate it doing. If you get one, let us know the results you experience with it.
Monte
