Originally Posted by duxthe1

As a professional M/B tech one of my pet peeves is finding the 13mm oil drain plug rounded over. I mean come on, if you don't actually have a metric tool set a 1/2 inch is a near perfect equilivent to a 13mm. Considering that either is probably the MOST COMMON BOLT SIZE EVER it must take someone special to round over all six corners of the hex with what I'd assume is a combination of channel locks, vice grips, and a hammer.