Abstract: A soft-sided cooler includes a flexible exterior shell, and a lower frame member secured to the upper edge of the exterior shell. A lid is pivotally mounted on the lower frame member with at least one hinge. A latch is mounted on the lower fame member, opposite from the hinge. The surface of at least one of the lid or the upper frame member smoothly slope outwardly toward the other then inwardly away from the other on either side of the latch, peaking at a point intermediate the latch and the hinge, to increase the sealing force between the lid and the upper frame one each side of the cooler, between the latch and the at least one hinge.