The white M-3250 could arguably be considered the most sought after and highest priced porcelain insulator of all time . Sadly the line that used them was long ago very well cleaned up and they appear to have mostly been hauled away and dumped at an unknown remote location back in the late teens when the entire line was upgraded. We only found evidence at a few scattered locations. Paul and I found parts of them and saved what we could find but not enough was found to make even a single complete insulator. Here is Paul pointing to the remnants of one core we found in Quebec after the National in Boston.