My son loved using the waterpik esp since he wears braces and is lazy about flossing his teeth. The waterpik made it a breeze, it was his new favorite toy. Unfortunately we damaged it while charging it in Russia. I thought that using a converter/adapter would work, like it does for my other appliances. Apparently not! The customer service representative told me that it is only to be used in America and that this is stated on the box but in very tiny fine print. I checked, and yes that's right. I am not the first to experience this. The company sent me a new waterpik gratis to my US home address (a pro!). But we need to buy a new one in Russia where it is double the price. Please make the fine print less fine!