What lock is best for a container?

The decision in front of you

You already have the hard part covered: every container we sell or rent ships with a welded lockbox over the lock point, standard, no extra charge. The decision left is entirely yours, which padlock goes inside it, and that one choice does more for your security than anything else on the box.

The real question is not brand or price point. It is whether the lock you buy is built to sit inside a recessed shroud, or whether it is a general-purpose padlock that happens to fit.

The deciding factor: shackle exposure

A lockbox protects whatever is inside it, but a padlock with a long, exposed shackle can still leave a sliver of metal reachable through the gap, enough for a bolt cutter to find purchase. A puck lock has no shackle at all; the shrouded body itself is the locking mechanism, so there is nothing to grab from outside. A shrouded-shackle padlock hides the shackle inside its own housing, which does the same job with a more familiar key-and-body design.

• Puck lock: round, low-profile, no external shackle, built specifically for recessed mounts
• Shrouded-shackle padlock: hardened body with the shackle recessed inside the housing
• Both are sized to sit fully inside the welded lockbox already on your container
• A standard padlock with an open shackle defeats much of what the lockbox is built to stop

What not to buy, and why it matters more than it seems

The lockbox does its job whether the padlock inside it is a ten-dollar hardware-store lock or a hardened one, right up until someone tests it. A soft-body lock can be sheared with a hand tool even when it is tucked inside a good shroud, because the shroud protects the shackle from cutters, not the lock body from a hammer and chisel. Spend the extra money here. This is the one piece of the whole arrangement you go out and buy, so buy well.

How the lock and the lockbox work together

Neither piece does much alone. A lockbox with a weak lock inside it still leaves the weak lock exposed to whatever gap the shroud does not cover. A hardened lock with no lockbox around it is still just a padlock hanging in the open for a bolt cutter to reach. Together, the welded steel shroud and a hardened puck or shrouded-shackle lock take the easiest attack off the table entirely, which is exactly why we build every container with the lockbox already on it.

Beyond the primary lock

Want a second padlock on the doors? A hardened hasp can be welded at a second position, so two locks have to be defeated instead of one. That is worth doing for higher-value loads or a jobsite that has already lost tools, and the price depends on the doors and the hardware, so it gets figured job by job. For most storage and jobsite use, one good lock in the lockbox that already comes standard is plenty.