Metal roof above sheathing ventilation system

A spacer comprising:

• a rigid body having a first end, a second end opposite the first end, a top surface extending between the first end and the second end, and a bottom surface extending between the first end and the second end and opposite the top surface, the first end and the second end defining an outer perimeter around said rigid body that is rounded at each of the first and second ends;
• an outer wall extending downwardly from the bottom surface along the outer perimeter to an outer wall edge, the outer wall including an outer wall exterior surface and an outer wall interior surface, the outer wall edge extending between the outer wall exterior surface and the outer wall interior surface;
• an interior wall extending downwardly from the bottom surface to an inner wall edge and spaced inwardly from the outer wall, the inner wall including an inner wall exterior surface and an inner wall interior surface, the inner wall edge extending between the inner wall exterior surface and the inner wall interior surface;
• and
• a primary fastener opening in the rigid body located between the first end and the second end, the primary fastener opening extending from the top surface to the bottom surface and defining a primary fastener ridge, the primary fastener opening being sized and shaped to receive a roofing panel fastener;
• wherein the inner wall edge and the outer wall edge are coplanar.