This is an example of a defender fouling the shooter. A defender cannot bring their arm(s) down out of their vertical cylinder to cause contact even if they had established initial legal guarding position. In this example, defender Blue 1 establishes an initial legal guarding position with his arms vertical within his cylinder while guarding White 21 on a drive to the basket. Blue 1 then drops both arms out of the vertical and makes illegal contact with the arms of White 21 as he shoots the ball. This is a hands foul by Blue 1.