We were carpet cleaners the last fifteen we worked. One of our clients wanted to see if the cat sprayed anywhere. We have a "black lite" which will show the salt in urine. ALL OVER THE LIVING ROOM, she wanted to ck the bedroom, as we walked-by the bathroom you could see the "salt" all over the walls, on top. On the sink, in the sink. Call me what you want, I really don't care, I SIT DOWN TO PEE!