Master Lock Pro Series Hidden Shackle Padlocks, Keyed Alike 6271NKA-1 w/BumpStop Technology

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. ProSeries Reinforced Zinc Die-Cast Why Zinc Castings? For countless decorative and functional applications no other material and process can match the properties and economics of zinc die casting. Toughness: Few materials provide the strength and toughness of zinc alloys. Impact resistance is significantly higher than cast aluminum alloys, plastics, and grey cast iron. Strength & Ductility: Zinc alloys offer high strengths (to 60,000 psi) and superior elongation for strong designs and formability for bending, crimping and riveting operations. Anti-Sparking: Zinc alloys are non-sparking and suitable for hazardous location applications such as coal mines, tankers and refineries