I couldnt find the $30.00 epoxy. I think the sales person might have been mistaken and misquoted the $ amount. I think the $3.00 priced epoxy from lowrance that you saw is what he meant. My search also came up with this. We recommend a 2-part hard setting epoxy, Non Metalic, Non-Porous, preferably ours, but other alternative like plastic Welder, Power Epoxy or True-Bond from True Value hardware stores will also suffice. Glynn