As a rule of thumb, if your water supply is normal water also known as fresh/ soft water, you can pretty much use any model of instant shower that pleases you; without worrying about damaging the heating element.
-18%
Original price was: KShs 3,300.KShs 2,700Current price is: KShs 2,700.
-6%
Original price was: KShs 2,500.KShs 2,350Current price is: KShs 2,350.
With normal/ fresh/ soft water, you can use any instant shower/ heater without worrying about the element. With proper installation/ use, a good quality instant shower will serve you for a very long time.