Abstract: A mold used to form a latex lid for covering a beverage cup includes a body having a top forming face and a side forming face extending around and turning downward from the top forming face, a stubby projection which has a rounded surface, provided on the top forming face, a shallow recessed fink provided in the top forming face around the stubbing projection. In forming the latex lid, the stubby projection creates a thinned area in the latex lid which facilitates the insertion of a straw, and the shallow recessed sink provides a thickened reinforcing ring around the thinned area. A blind hole may be provided in the stubby projection to create an internal bursting force which can produce a hole in the thinned area.