A fluid discharge valve has a first part 106 with a valve seat (110, figure 4) and a second part 124 with a flow conditioner (146, figure 14). The two parts screw together and each is broadly tubular with a through bore 118 which is sealed when the flow conditioner sits against the valve seat. The first part has a radial flange 116 located between its ends. The flange surface which faces the second part bears at least two rotational detent elements (122, figure 4) which engage with corresponding elements 136 on an end face 126 of the second part when the valve is closed. This releasable engagement inhibits movement of the second valve element from its closed configuration. There may be twice as many detent elements on one face as on the other and preferably the first part is held captive inside the second by a radial protrusion 158. The valve may be used for releasing liquid from a urostomy pouch (102, figure 1).
