The system described here is a bolt-type seal lock which includes a bolt, having a U-shaped shaft with first and second end portions; and a locking body having a passageway therethrough with first and second open ends on opposite sides of the locking body for receiving the first end portion of the shaft...http://www.google.com/patents/US7828342?utm_source=gb-gplus-sharePatent US7828342 - Reusable locking body, of bolt-type seal lock, having open-ended passageway and U-shaped bolt
