Point firing is similar to Quick Kill, with the sights not being used. The target is usually in close range, between 1–21 feet, in a life-or-death situation. Chuck Klein defines instinctive combat shooting as "the act of operating a handgun by focusing on the target and instinctively coordinating the hand and mind to cause the handgun to discharge at a time and point that ensures interception of the target with the projectile." The shooter should focus on a small point, like a button, stain or corner, not the attacker or target in general. This intense focus is tunnel-vision, which is widely discouraged, but is mandatory for the brief moment when the shooter transitions from deciding to shoot to the completion of shooting. Additional threats and innocents who may be hurt are scanned before the decision to shoot is made, and can be seen in peripheral vision. Between the point at which one decides to shoot and completion of the shot(s), full concentration, oblivious to everything else, is required. The time in which the shooter is engaged in tunnel vision only lasts a matter of milliseconds. Race car driver Phil Hill says, "True concentration is not aware of itself." There are no rigid requirements for positioning the body, feet or arms, as the practical use of this technique requires the shooter to be able to shoot from any position, though it is recommended that the shooter practice the technique using common target shooting stances.