Master Lock
Master Lock S31BLU Lockout Padlock Blue 1 1/2 in
Key-retaining lockout padlock with a 1 1/2 in stainless-steel shackle, corrosion-resistant thermoplastic body and non-removable key for safety isolation
- TypeKey Retaining
- Key-retaining design prevents accidental unlocking
- Thermoplastic body resists corrosion in harsh environments
- Stainless-steel shackle withstands cutting and prying attempts
- Keyed-different cylinders ensure individual access control
- Compact 1 1/2 in shackle fits tight lockout points
Master Lock S31BLU Lockout Padlock
The Master Lock S31BLU is a blue thermoplastic lockout padlock built for industrial safety procedures. Its key-retaining design prevents the key from being removed until the shackle is locked, enforcing proper isolation steps. The 1 1/2 inch stainless steel shackle provides corrosion-resistant strength for demanding environments. Supplied labels allow clear identification of the responsible worker.
Check shackle dimensions and keying requirements
Verify that the 3/16 inch shackle diameter and 5/8 inch horizontal clearance fit your lockout hasps, valve covers or breaker toggles. The 1 1/2 inch vertical clearance must suit the specific isolation points on your equipment. This model is keyed different, so each padlock opens only with its own key; order keyed-alike sets separately if your procedure requires one key for multiple locks.
Replaces standard padlocks in lockout programmes
Unlike conventional padlocks, this unit holds the key captive while unlocked, preventing accidental re-energisation. The thermoplastic body resists chemicals and temperature extremes better than laminated steel bodies. Upgrade when your safety audit demands non-conductive, key-retaining hardware with permanent identification labels. Workers needing a single key for multiple lockout points should choose a keyed-alike alternative instead.
Highlights
- Key-retaining design prevents accidental unlocking
- Thermoplastic body resists corrosion in harsh environments
- Stainless-steel shackle withstands cutting and prying attempts
- Keyed-different cylinders ensure individual access control
- Compact 1 1/2 in shackle fits tight lockout points
Specifications
| Brand | Master Lock |
|---|---|
| Type | Key Retaining |
Questions about this item
What comes in the box and what must I buy separately?
The padlock includes labels; no keys or additional hardware are mentioned as included.
Which version should I choose for my lockout needs?
This model is keyed different with a blue thermoplastic body, 1 1/2 in stainless steel shackle, and key-retaining operation.
What does the 1 1/2 in shackle clearance mean when installed?
It provides 1 1/2 in vertical and 5/8 in horizontal clearance for locking through hasps or chain links.
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