The most popular type of screwdown for baseball cards on the market today. This new and improved version has a recessed arrowhead in each corner so that the baseball card's corners are never touched. It also has a white frost on all four sides of the card which makes the baseball card stand out better. Invented by Pro-Mold in 1993.
Strengths: Small and compact compared to traditional style four screw screwdowns which allows for storage of many in smaller spaces particularly in monster boxes or shoe boxes. What made the one screw screwdown popular is the fact that you get all the benefits of a four screw, as far as protection of the baseball card goes, but with only having to use one screw instead of four.