About Our Padlocks
Security Ratings and Corrosion Resistance
Security Rating
Use this rating as a guide to how well a padlock will resist attack, either forced (cutting, drilling, etc.) or surreptitious (picking, bumping, etc.) Padlocks at the lower end of our 1 to 5 scale should be used only as a deterrent in well supervised environments.
Corrosion Resistance
This rating indicates how well the padlock will endure exposure to weather and/or corrosive environments. While corrosive elements in the environment will do little to reduce padlock strength in the short term, they can attack the tumbler and other internal components and compromise the mechanical integrity of the padlock. Moisture and salt are the biggest environmental culprits. Padlocks rated 1 on our 1 to 5 scale should be used only in dry, indoor environments. Padlocks rated on the higher end of the scale are more appropriate for outdoor use and in more severe weather applications.
Keying Options
Keyed Different (KD)
Each padlock has a different key that will not open other locks, even if they are the same model. Locks are commonly sold this way.

Keyed Alike (KA)
All padlocks in a given set have an identical pin arrangement and open with the same key.

Master Keyed (MK)
In a master-keyed system, a single master key opens all locks in the set although each lock has its own unique key. Master-keyed locks are in tended for supervisory or emergency access.

Dimensions & Specifications Key

Padlock Glossary of Terms
- Barrel-Key Lock
- A lock using a cylindrical pin arrangement and a barrel-shaped key with key cuts around the circumference of the shaft. Barrel-key locks are extremely difficult to pick.
- Body
- The lower part of the padlock housing the cylinder and the shackle locking mechanism.
- BumpBlock
- An exclusive Move ’N Store technology that prevents the use of a bump key to open the padlock.
- Case Hardened
- Layer of tempered metal applied to the outside of the shackle for added cut resistance.
- Combination Lock
- A lock opened by pushing buttons or by the rotation of dials or disks.
- Cylinder
- The core of a padlock where the key is inserted. Better quality locks have brass or bronze cylinders to resist corrosion.
- Double-Locking Plates or Heel-and-Toe Locking
- The shackle is secured at both ends, referred to as heel and toe, with plates or balls that slip into indents at each end. Better padlocks offer this increased security feature.
- Hardened
- The entire shackle is heat-treated for added strength.
- Key Differs
- The mathematically possible number of different key cuts or pin arrangement combinations with a given number of pins and differing pin lengths. For example, a 5-pin lock using 5 different pin lengths would have a possible 3,125 key differs (55).
- Key Retaining
- The key cannot be removed while the lock is still open.
- Keyed Alike (KA)
- All padlocks in a given set have an identical pin arrangement and open with the same key.
- Keyed Different (KD)
- Each padlock has a different key that will not open other locks, even if they are the same model. Locks are commonly sold this way.
- Master Keyed (MK)
- In a master-keyed system, a single master key opens all locks in the system although each lock has its own unique key. Master-keyed locks are intended for supervisory or emergency access.
- Mushroom Pins
- A pin design which makes picking more difficult. A pin cylinder design where some or all the pins have a “mushroom” shape that will allow the pin to move slightly from side to side and create a false “feel” to the picker.
- Paracentric Keyway
- A key design with a curved rather than straight cut edge which, when used as random left and right curves, effectively doubles the number of key differs.
- Pin Tumbler
- A type of cylinder which, when the key is inserted, pushes down four to six pins to their correct positions, opening the lock. An incorrect key will pushpins too far or not far enough, and the lock will not open.
- Shackle
- The looped portion at the top of the padlock which swivels open and closed. Some models offer different shackle sizes to accommodate door hardware.
- Shear Line
- The point at which the top and bottom pins of a pin tumbler lock meet to allow the cylinder to turn.
- Wafer Lock
- A lock similar to the pin tumbler that uses disks that must be raised to a certain height to allow the cylinder to turn.