A male fastener element extends integrally from a planar base and includes a primary engagement hook and a secondary engagement structure. As a result, charge is alleviated at a location where junction leakage is caused in a time period shorter than that of a normal portion and therefore, a potential difference is produced between the normal portion and a failed portion and is observed in a potential contrast image as a difference in brightness. As a vehicle load changes, the HEC adjusts the battery current flow. The solution comprising the oligomeric polycarbonate can also be pre-heated under pressure to a temperature above the boiling point of methyl salicylate and subsequently fed to a devolatilizing extruder equipped for rapid flashing off the solvent. The present invention also relates to the process to make such fluids.