Originally I saw an ad on SBS i think, not sure? Anyway, I ended up buying a dual sensor model for my boat and it has helped me diagnose my overheating problem and now that that’s resolved I’m  delighted to have the extra protection that a display and alarm offers. I was so impressed with the one I bought for my boat that my most recent order (a single sensor model) is one I’ve ordered for my very non-technical brother for his much loved Toyota Prado.