the barrel and bead are placed below the target (the amount below depends on whether the target is rising or falling) and slightly ahead of the target if there is lateral movement. This method of aiming is not as precise as that of a front sight/rear sight combination, but it is much faster, and the wide spread of shots can allow an effective hit even if there is some aiming error. Some shotguns also provide a mid-bead, which is a smaller bead located halfway down the rib, which allows more feedback on barrel alignment. Some shotguns may also come equipped with rifle-style sights — typically shotguns intended for turkey hunting have this arrangement. Types Open sights Open sights generally are used where the rear sight is at significant distance from the shooter's eye. They provide minimum occlusion of the shooter's view, but at the expense of precision. Open sights generally use either a square post or a bead on a post for a front sight. To use the sight, the post or bead is positioned both vertically and horizontally in the center of the rear sight notch. For a center hold, the front sight is positioned on the center of the target, bisecting the target vertically and horizontally. For a 6 o'clock hold, the front sight is positioned just below the target and centered horizontally. A 6 o'clock hold is only good for a known target size at a known distance and will not hold zero without user adjustment if these factors are varied. From the shooter's point of view, there should be a noticeable space between each side of the front sight and the edges of the notch; the spaces are called light bars, and the brightness of the light bars provides the shooter feedback as to the alignment of the post in the notch. Vertical alignment is done by lining up the top of the front post with the top of the rear sight, or by placing the bead just above the bottom of the V or U-notch. If the post is not centered in the V or U notch, the shot will not be accurate. If the post extends over the V or U-notch it will result in a high shot. If the post does not reach the top of the V or U-notch it will result in a low shot. Patridge sights, named after inventor E.