High Security: Master Lock's Pro Series padlocks feature high security with keyed alike locking mechanisms for added protection. Durable Construction: Made from steel with chrome plating for added durability and resistance to corrosion. Easy to Use: Designed with a hand control for quick and easy operation. Multiple Uses: Can be used for securing doors, cabinets, storage containers, and more. Trusted Brand: From Master Lock, a leading brand in security products for over 100 years. FEATURING BumpStop TECHNOLOGY - Lock bumping a surprisingly simple method of breaking in through locked doors and padlocks - is undoubtedly the newest emerging threat to personal property security. And virtually all locks in use today are particularly vulnerable to bumping. Until now. BumpStop Advanced Cylinder Technology employs an innovative, patent pending design which utilizes a unique reverse rake tapered driver pin, high performance springs and tightly machined cylinder chambers. During a bump attempt, this design prevents the transfer of force from the bump key to the pins and therefore blocks rotation of the cylinder so that the lock remains locked.