Dude, just use synthetic urine. It does work and it does work all the time. The only occasion somebody will fail is if the specimen is not at the right temperature (90-100 degrees Fahrenheit). I'd be willing to bet they're just selling you a mix of synthetic urine...who's gonna spend $500 at a lab to prove them wrong? Anyhow, I've used synthetic urine for at least 5 piss tests and the only 1 I failed is the one that I took when I was so hungover that I poorly prepared and my sample was too fuckin hot to be accepted (GODDAMN UNRELIABLE HEAT PADS!) and then they offered me to retake it with one of their employees watch me piss. I declined I use to have the urinator that they sell for $150 which regulates the temperature at 98 degrees through a digital monitor / heat element powered by a 9 volt battery. Worked fucking awesome...then I loaned it to a friend and never saw that motherfucker again! If you have to really pass a test for something like keeping your job or even getting a good job you're applying for...pony up the bucks and get the urinator. They sell another thing called the whizzinator which is similar with a fake dick but it also relies on those crappy organic heat pads that can easily (and I mean very easily) put your temp over 100...and then when it touches your skin at full heat....burns like a bitch.