since the spacing members 100 engage one another to lock in a face to face configuration there are several other additional advantages specifically this locking feature can be bi directional making part orientation irrelevant moreover the locking feature can be adjusted so as to be implemented under various loads for example with no more than 150 pounds static load and no less than 50 pounds static load placed over any corner of the pair of spacing members 100 moreover because the conical frustums 104 are hollow the interiors of the conical frustums 104 are accessible through openings not shown within the planar member 102 these openings not shown allow for the spacing members 100 to be stacked on top of one another this stackability or nestability reduces the amount of space required for storing the spacing members when not in use anti jam ledges not shown can also be located within the conical frustrums to assure ease of denesting moreover individual or nested bulkhead stacks can be accessed and maneuvered by forklift on two flat ledges between the three conical frustums 104 another advantage is that rotation of one spacer on top or beneath 180 degrees should produce a vertical gap between bulkhead parts to enable separation and lift by fork truck blades having thus described the present invention by reference to certain of its preferred embodiments it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that.