One (1) Locks Keyed Alike w/ 2 Keys. A shorter 1-1/2" (38mm) shackle version available - search: M5NKASTSLF These locks feature the BumpStop Advanced Cylinder Technology. (for explanation see more product details below). If you order two 1-packs or any multiple of this lock we will automatically key them all the same. SPECIFICATIONS: 2" (51mm) wide laminated steel body for superior durability. 2-1/2"L (64mm) x 3/8" thick octagonal BORON CARBIDE shackle is 50% harder than hardened steel. COMMERCIAL MAGNUM offers a higher level of weatherability and security for applications in outdoor, corrosive and caustic environments. Stainless steel body cover and top and bottom plates for exceptional weather protection. Chrome-plated shackle for excellent rust resistance. Superior pry resistance with dual-ball bearing locking. 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.inquire and we can normally have them in a couple of days.