US Patent 10561194 Bike helmet with improved vent cover

A helmet that includes vents in the shell and removable plugs that may be positioned in the vents to provide an airtight seal while maintaining the aerodynamic shape of the helmet. The vent has an outer vent opening in the outer wall surface of the shell and an inner vent opening in the inner wall surface of the shell. The plug includes a resilient lower surface and an upper surface opposite the resilient lower surface. The resilient lower surface has a lower peripheral lip that compresses when the plug is pushed through the outer vent opening and the inner vent opening and that subsequently expands after the lower peripheral lip passes through the inner vent opening so that the lower peripheral lip engages a portion of the inner wall surface of the shell. The upper surface has an upper peripheral lip configured to conform to a portion of the outer wall surface of the shell when the plug is inserted in the vent.