Ever since I tried a Toto in Japan, I've become fascinated with these bidet seats, and have since become an expert on them, after building my own bidet seat review blog and bidet seat store to resell Brondell products (which are among the top brands). I've learned that most of the top end bidet seats have complex nozzle retraction and sanitization systems. The Brondell Swash 1000 we sell has stainless steel nozzles treated with "silver oxide nano particles" that resist bacteria, and most models have systems that rinse the nozzle before and after each use. The nozzles typically retract when not in use so that they're not in the line of fire of human waste.