Skeleton Key Quatrefoil Bow Metal Sign

About the Quatrefoil Bow design

Its outer edge forms a diamond with softened corners, pointed at the far left and flaring smoothly into the shank on the right. Inside sits a round opening with two tiny round pockets, one pushing up toward the top corner and one down toward the bottom, like the heads of two pins. Along the underside of the long shank hang three stepped teeth, a short square one first, then two deeper ones with notched corners, while the rounded tip runs on past the last.