master key cylinder lock

Listings describe these padlocks as suitable for keyed‑alike applications and note they "can be pinned to customers key in minutes." In other words, keyed‑alike models can be set so one key opens multiple locks, and re‑pinnable cylinders can be reconfigured to match a customer’s key—often done quickly using a universal pin keying tool referenced in the product details.

Body materials listed include laminated steel, brass, and vinyl‑covered aluminum. Shackles are commonly described as hardened steel or hardened boron alloy for improved cut resistance.

Common mechanisms include 4‑pin cylinders with pin‑tumbler designs, double‑locking or dual locking lever/ball systems, and some models list an automatic locking lever feature.