This the Acorn Corbel rail, a new variation of spindled railing.  This rail is 2 1/4" high at the rails and the acorn sets 1/2" below the rail.  It is unique in that the bottom rail is cut into the back of the spindles and glued.  When set atop a cabinet the acorn hangs out and below the rail.  Spindles are 3" on center.  Available in 4, 6, & 8' lengths.