What is the Best Type of Chain for a Closed Shackle Padlock?

A closed shackle padlock provides excellent protection against bolt cutters and saw attacks by shielding most of the shackle within the padlock body. The trade-off is reduced space to attach fittings such as chains. However, you can still use a chain, provided you choose the right type. Standard chains that are cut to length in hardware stores usually have two identical-sized end links. These are often made from mild, galvanised or stainless steel, which can be cut quickly with bolt cutters. Because both end links are the same size, they also cannot fit properly into the restricted space of a closed shackle padlock.

Choose a Hardened Steel Security Chain

For closed shackle padlocks, you need a hardened steel security chain with a looped end configuration. This means one end link is longer, allowing the smaller link on the opposite end to pass through it. This creates a secure loop that only requires one link to fit inside the padlock — ideal for restricted shackle openings.

Recommended Chains

The Abus 6KS65 is an excellent example of this type of chain. It is made from case-hardened steel, available in various lengths and link diameters, and features one extended end link. This allows it to work perfectly with closed shackle padlocks while maintaining strong resistance against cutting attacks.

For heavier-duty applications such as securing gates, motorcycles or machinery, the Abus 12KS120 looped chain is a strong upgrade. It is thicker, heavier and often paired with a ground anchor to secure it to a fixed point. Most high-security chains include a fabric or protective sleeve to prevent damage to paintwork and surfaces.

Key Takeaway

When using a closed shackle padlock, a standard chain will not work effectively. Choose a hardened steel chain with a looped (extended link) end design so that only one link needs to be placed inside the shackle. This ensures both a secure fit and a significantly higher level of protection against attack.