The present invention concerns a tap for drainage of a urine collection bag, comprising a housing (1) having a first and second flow passage (101, 102) and a substantially cylindrical inner space and a housing bottom a rotatable valve member (2), which is rotatably mounted in the housing, is provided with a flow passage (20), and may be rotated in the housing (1) between a closed valve position and an open valve position where flow communication between the first and second flow passages (101, 102) is provided wherein the inner space of the housing (1) is provided with first rotation limit stop means (11) which cooperate with second rotation limit stop means (23) on the valve member (2) for limiting the angular displacement of the valve member (2) in the housing (1).
