Received the Nel Hunter coil for my F19 yesterday. I haven't had it in the field yet but this is what I've found so far. The Standard 11" Bi-Axial coil off my Gold Bug Pro weights 16.8 oz. The Nel coil which measures 8.5" x 12.5" weighs 20.4 oz. an increase of 3.6 oz. The Nel came with a coil cover, velcro cable tie and a nylon bolt to attach it to the lower rod. The bolt was too large a diameter to go through the mounting tabs. The Bolt measured .312" the hole was about .250". Out came the drill and now the bolt fits. The bolt is also to large to go through the Fisher lower rod but I use a White's rod as it's longer and the mounting hole is larger in diameter. The Nel coil also comes with a neat little cap that is attached to the cable and it screws onto the plug to keep it clean. The coil cable is the largest diameter coil cable I've seen. I thought I was wrapping a garden hose around the shaft. In air tests it looks to be about 1" deeper on all coins than the Fisher 11" coil running the Sens at 100. The difference in weight may be offset in that the mounting position in closer to the center of the coil and not out near the end like the Fisher coil. This coil will most likely be my choice for dry beach hunting so the Field test will probably be awhile off. If it works out, another may have to be purchased for my F75.