As you can see, a 3 technique is a defensive lineman who often sets up on a guard's outside shoulder. A defensive lineman who uses the A-5 technique often positions up on the outside shoulder of the offensive tackle. The A-5 is most effective at stopping the run because it prevents the offensive line from pulling together and forming a wall against which the defense can rush the quarterback. The A-5 is used primarily by 4-3 defenses to stop the run. However, some 3-4 teams may use an A-5 player when they want to put more pressure on the quarterback. Because there are more players aligned along the line of scrimmage, the A-5 is less likely to be blocked out of position by a running back than other techniques are. Instead, the A-5 defender tends to stay with his assigned running back all the way until the ball is carried away from him. At that point, he can flow back into the play if necessary. A defensive end using the A-5 technique sets up about three inches outside the left edge of the offensive line. His goal is to stop the run by taking away any holes created by the guards. Since the A-5 player is usually not involved in pass protection, he needs to be strong enough to handle double teams. This means he should play on the smaller side (less than 300 pounds).