Bolt Seals offer high security and tamper evident solutions for transporting cargo and other highly valuable items. Bolts seals come in two pieces and are made of low carbon galvanized steel wrapped in a heavy-duty ABS plastic polymer shell. To use, simply break apart the locking cap from the shaft and click the two pieces together to engage the lock. Often, then shaft will be fed through a locking mechanism of a door. Once fed through the locking mechanism, the locking cap is pressed onto the end of the shaft. An audible click will be heard to assure proper locking has happened. As an increased security measure both shaft and cap have a squared end to ensure the bolt can not be spun. This is a ISO 17712:2013 Compliant Seal.