Abstract: A pair of underpants include two pieces of flexible material that are attached to the front of the underpants. The attached pieces are superimposed on each other and cover a slot that can act as the flies. The edges of the attached pieces which are furthest from the waistband are slanted with respect thereto in opposite directions and intersect, forming a re-entrant angle, in the vicinity of the opposite end of the slot from the waistband.