Sighting hole with reflectorized screen. Larger size signaling mirror. Pocket size. Scratch resistant. With the sun as light source, a mirror can be used to signal by variations in the orientation of the mirror. The signal can be used over long distances, possibly up to 36 miles on a clear day. Mirrors can also be used for rescue, especially to attract the attention of search and rescue helicopters. GI Government Issued style. Signal mirror 4 x 5 inches. Dimensions: 4" x 5" (inches).