I have a Royal Sabre. A few years ago a friend gave me a "4 coil to go with my Silver umax when I purchased it from him. I finally tried it on my Royal and it worked very well. Since the Royal is a 12 khz detector-would the 5.75 coil work on it also? The "4 is a tad too small when I search larger areas and my "8 coil that came with the Royal was damaged beyond repair . And also, if I wish to search larger areas at times, would I be happier with a "7 or the 5.75. I can set the Royal to work just as the Golden w/different tones by adjusting the knob (disc level 1) and love to use it this way under less trashier situations. Thanks to everyone .