All steel high-security keyless bolt lock, sequentially numbered. +2,500 Lbs. Breaking Strength. Keyless, single use bolt locks provide a high level of security and tamper-evidence. Steel, heavy-duty, high-security bolt seal for trucks, cargo containers, etc. wherever high-security and tamper-evidence is required. C-TPAT ISO 17712:2013 Compliant. Meets US Custom and Border container seal requirements.