Master Lock 1-3/4" (44mm) Wide Laminated Steel Pin Tumbler Padlock with 2-1/2" (64mm) Shackle

KD (keyed different) means every lock gets its own key, so one key opens one lock. KA (keyed alike) means all the locks on your order share a single key, which is what you want when one person has to open a run of gates, cages or meter boxes without carrying a ring of keys. Those are the two ordering choices on the Master Lock 40 Series laminated steel padlock, and they are decided at order time, not afterward.

Go by two numbers. The shackle stands 2-1/2 inches tall, which is the vertical clearance you get for a hasp staple, chain link or cage loop, and the inside shackle width is 3/4 inch, which is what has to clear the thickness of what you are locking through. A thick hasp tongue or a heavy chain that needs more than 3/4 inch of bite will not seat.

No. The 40 Series laminated steel padlock uses a non-rekeyable 4-pin W1 cylinder, so it cannot be pinned to an existing master key system. If you are standardizing a property on one keyway, order these keyed alike on a single key code instead and run them as their own group, or specify a rekeyable padlock cylinder for the openings that must sit on the building system.

The body is laminated steel, the shackle is hardened steel for cut resistance, and the shackle is held by dual ball bearing locking, which is what resists a pry bar twisting the lock off the hasp. Master Lock calls it commercial grade with protection against drilling and prying. For a self-storage unit, tool cage, gate or fence application that is the normal duty level for a laminated padlock.

There is no fixed limit on the number of 40 Series padlocks you can run on one key code, and that is the point of the KA option for a property manager handling multiple doors or gates. What matters practically is quantity against a single stocked code, so it is worth allowing a substitute keyed alike number when you place a large order, which is an option on the order form.

The 40 Series padlock runs a 4-pin W1 pin tumbler cylinder, which gives a workable number of key differs and basic pick resistance for gates, sheds, lockers and general property use. It is not a high security cylinder, so for an opening where forced or covert entry is a real threat you want a padlock with a high security rated cylinder and a shrouded shackle rather than this one.