Presenting the ultimate transducer-mounting system for the sit-on-top fishing kayak. Fits all HDS, Elite, Mark, and X-Series Lowrance Skimmer transducers, both 83/200kHz and 455/800kHz DownScan Imaging models, as well as earlier 1" 200 kHz transducers (which are sold separately). Not for 50/200kHz Skimmer transducers. Its easy to install in most any scupper opening with few tools, and without messy adhesives as with shoot-thru-hull transducer mountings. Best of all, the new Lowrance Scupper Mount positions the Skimmer transducer so its totally submerged in the water youre fishing. That guarantees maximum sonar signal return sensitivity, producing the absolute clearest underwater returns. Compatible scupper hole dimensions: Diameter: 1 1/2" max./15/16" min.; Depth: 9 1/4" max./1 19/32" min.