Urine bags with drain holes are connected to a catheter or urinal condom and collect the drained urine. Backstops prevent the urine from flowing from the bag back into the urinary tract.
The capacity can vary between 500 and 1300 ml. A drain valve allows the bags to be emptied without having to be disconnected from the urinary tract. There are special urine leg bags which have a kink-free inlet even with an angled shape and adapt to the sitting posture. Bed or night bags have a significantly higher capacity than other urine bags (up to 2000 ml).