The most straightforward entry on the list and a quite literal depiction of Master Lock’s “Tough under fire,” slogan, this ad and subsequent Super Bowl spots accounted for nearly all of Master Lock’s annual ad budget. The commercial first aired during Super Bowl VII. The plot: A sharpshooter blows a hole through a Master Lock, and it still doesn’t open. I’m assuming this ad is shown in freshman level advertising classes as a matter of routine.