A fitment for use as a pour spout for a paper carton or flexible bag for liquids and powders has a flange which may be welded around a hole in the carton. A spout projecting outward from the flange is provided with a removable membrane integral with an inward projection positioned on the interior of the spout approximately midway of its height. Preferably the membrane is concave. A horizontally disposed pull ring is attached to the membrane by a connector so that pulling the ring removes the membrane by fracturing the tear line at the juncture of the outer edge of the membrane and the projection. A cap snaps over the spout and may be removed by unscrewing the complementary threads on cap and spout. A tamper-evidencing band frangibly connected to the lower edge of the cap skirt engages the exterior of the spout so that the cap cannot be removed without breaking the fragible connection.