Believed to be proof cards, black and white, blank backed cards such as this mirror the E97 Briggs Co. color cards issued by the C.A. Briggs Co of Boston.  Valued considerably higher than the color versions, the black and white proofs are much tougher to find.  This example of Abby McConnell's card has been graded POOR 1 by SGC, due to the upper right corner clip, severe edge wear, and heavy creasing.  Despite the wear, a very difficult card too find in any grade.