the header to install the assembly 18 on a header the assembly is positioned so that the clamp end of each vertical wire 20 is generally aligned with an associated opening 30 in the header the leading ends of the clamp ends are then pushed into the opening 30 with such movement being facilitated by the beveled surface 32 whereby both the cam portion 38 the shoulder 40 and the leg 42 are compressed toward the first leg portion 36 of the clamp end the vertical dimension of the opening 30 and the spacing between the leg portion 36 and the top most surface of the cam portion 38 which forms the shoulder 40 is such that the clamp end can be pushed through the opening 30 without difficulty once the shoulder portion 40 has cleared the opening 30 the resiliency of the wire material will cause the shoulder 40 to snap up behind the adjacent surface of the header and the leg portion 42 to tightly engage the opening the positioning of the shoulder following such snapping action prevents the withdrawal of the clamp end unless and until the cam portion 38 is compressed to permit withdrawal of the clamp end from the opening it will further.