A defense structure and methods of use for penetrating the defense structure with a projectile from a first side and preventing a projectile from penetrating the defense structure from a second side. The defense structure comprising a plurality of wedges arranged to rotate and abut each other using a tensioning member, such as a spring. Ballistic and resilient members are provided on a rear surface of the plurality of wedges to prevent a projectile from penetrating the defense structure through deflection and/or adsorption of the projectile. A gap is formed between at least two of the plurality of wedges when a projectile is urged between the plurality of wedges from the first side. The tensioning member urges the plurality of wedges to rotate and abut each other after the projectile passes through the gap. The defense structure may be partially concealed within a structural element.