Hobie hatches are designed to have a better seal. The lids also hinge open, so you never lose the lid. Designed with a cork-screw-like mechanism for closure, a simple twist of the handle opens or closes the hatch. As the screw pulls down the hatch, you get a tight seal on the O Ring seal against the inner cylinder. The hatch seals around the edge of the cylinder and does not have to be held down against a flat surface to seal. This allows the hatch to seal even if the lid is partially open or tipped. Flip the handle into the recess to lock it closed. Available in 6 and 8 diameters. These hatches are now standard equipment on all Hobie Kayaks.