We will now only allow the Striper to play inside the Tackle Box. He does not need to be covered by anyone on his outside but he must be inside the Tackle Box. The Tackle Box defined is: the space that spans the length of the offense line, from the left tackle to the right tackle.
The first drawing included is an explanation of the Tackle Box along with the lettered Gaps and the numbered Defensive Techniques.
A Defensive Striper will be allowed to line up on the outside eye/shoulder pad of the Offensive Tackle with his inside eye/shoulder pad. He will also be allowed to line Head Up on the Offensive Tackle. This is depicted in the second drawing.
A Defensive Striper will never be allowed to be Head Up, Outside, or Inside Shoulder of a TightEnd. This is depicted in the third drawing.
Finally, in keeping with the spirit of the rule, an Offense cannot shift their formation to leave a Defensive Striper outside of the Tackle Box to try to get a penalty called on the Defense. If you shift or trade, you do so at your own risk, per se.
Additionally, if somebody were to run a Single Wing, Notre Dame Box Offense, Unbalanced Line, etc then the Tackle Box will still be from the area where the Tackle would have normally been to the area where the player is currently playing the Tackle position is at. This is depicted in the last drawing.
The easiest way to think about this is, bottom line, a the widest position a defensive striper can play without penalty is a hard a 5 technique, as depicted in the first drawing.