Offensive tackles are extremely important for an offense and team. They are the guys who usually get no help outside of them to protect the quarterback. Most sacks are made from defensive ends, outside linebackers and cornerbacks coming off the edge. If they don't protect their quarterback and the quarterback gets hurt, the season is likely a lost cause.
A prototypical NFL offensive tackle is at least 6'5'', has excellent feet, long arms, great strength, good hand placement, keeps low, takes good angles to get to their man and can move. This is a pretty weak class of offensive tackles outside of Matt Kalil, Riey Reiff and Jonathan Martin. The rest have a lot of work to do to reach their full potential if they want to become NFL starters at some point in their careers.
Here are my top 10 offensive tackles in the 2012 NFL Draft.