a couple of months ago i posted a PISSINATOR UPDATE on this forum with all the pros & cons for the product. i would check that out & also visit their website PISSINATOR.com & read the info provided. using it was pretty simple. the strap is adjustable and its not too bulky to wear. putting it on in a car... i dont think i would have been comfortable doing it, unless it was a really big car, but if you have to then you have to. the urine is not in tablet form (never seen that before). it is dehydrated & in a powdered state which has to be mixed with distilled water. that can be done ahead of time but they say if its not used in 24-48 hours then you will have to freeze the urine and i wouldnt suggest removing the bag from the device. so you may not want to prepare it until you need it. once its ready to go, its as simple as pinching the shaft near the head, thats all. varying the amount of pressure on the valve will increase or decrease the flow. and stop pinching when you're done. dont forget to shake (really). a little urine gets trapped in the valve and you should shake that out. you can fill it with whatever you want; it comes empty so if you have the real stuff, use it.

hope this was helpful. peace.