Patent ID: 7685961
Filing Date: 2010-03-30
Classification: G01C

Abstract:
1. A survey marker, consisting of a head comprising a convex upper surface and a concave lower surface, said head including a center opening there through; a longitudinal rod; and a collar including a center opening there through and an exterior surface and an interior surface, said collar coaxially aligning with said center opening of said head, an upper end of said collar attaching to said concave lower surface of said head, said collar extending downward from said concave lower surface of said head, said center opening of said collar enclosing an end of said rod extending there through in a coaxial relationship, said rod affixing to a bottom end of said collar, said end of said rod extending through said center opening of said collar to a point equal to or less than an edge of said center opening of said head spacing said rod apart from said edge of said center opening of said head and said center opening of said collar forming annular groove there between.