Disposable urine bag for collecting urine

A disposable urine bag for collecting urine, said bag comprising an upper delimiting edge, a lower delimiting edge, and lateral delimiting edges, said edges delimiting a space in the bag, the upper delimiting area situated at the upper delimiting edge communicating with means outside the bag, and said lower delimiting edge comprising a single use drain valve with a first hollow element comprising compressible walls being able to stop the flow of urine when pressed against each other and allowing flow of urine when pressure is eased and a second element in extension of said first element, said second element being situated outside the delimiting edges of the bag, said first hollow element having a first drain mouthing communicating with said space in the bag and a second mouthing located adjacent said second element, said second element including a solid plate frangibly and directly connected to said first hollow element at said second mouthing and normally blocking said second mouthing-to define said single use drain valve, said second element with said solid plate being removable from said first element upon said frangible connection being broken to thereby discharge urine at said second mouthing, and an annular recess concentrically surrounding said solid plate.