Usually we will use the URO SYSTEM with the Silicone Catheter, it's for leading urine during the operation. Usually we will use the URO SYSTEM with the Silicone Catheter, it's for leading urine during the operation. We have prefilled syringes with 10% Glycerin + 90% Distilled water in the Uro System, the reason why we use 10% Glycerin + 90% distilled water instead of 100% distilled water is it ...