A lightweight barrier with locking devices at the top, middle, and bottom. Each barrier has an I-shaped male tab and a matching female slot. The I-shaped male tab is inserted into the female slot on an adjacent barrier. Locking pins are inserted through lower end upper extensions of the I-shaped male...http://www.google.com/patents/US6164865?utm_source=gb-gplus-sharePatent US6164865 - Interlocking barrier system with multiple securing mechanisms
