






Buy anything from 5,000+ international stores. One checkout price. No surprise fees. Join 2M+ shoppers on Desertcart.
Desertcart purchases this item on your behalf and handles shipping, customs, and support to SINGAPORE.
🔐 Lock it down, power up your safety game!
The Master Lock 493B Circuit Breaker Lockout is a compact, OSHA-compliant device designed to securely lock standard single and double toggle breakers rated up to 24 amps and 240 volts. Featuring a patented Grip Tight™ mechanism, durable powder-coated steel and polymer construction, it ensures reliable lockout in harsh environments while accepting all Master Lock and American Lock safety padlocks for versatile security.






















| ASIN | B004J173I8 |
| Best Sellers Rank | #10,600 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #4 in Lockout & Tagout Devices |
| Brand Name | Master Lock |
| Circuit Breaker Type | Standard |
| Current Rating | 24 Amps |
| Customer Reviews | 4.6 4.6 out of 5 stars (1,669) |
| Global Trade Identification Number | 00071649229725 |
| Included Components | Unit^Instruction Guide |
| Item Dimensions D x W x H | 5"D x 3"W x 1"H |
| Item Type Name | Lockout Tagout Device Circuit Breaker Lockout |
| Item Weight | 0.05 Kilograms |
| Manufacturer | Master Lock |
| Model | 493 |
| Mounting Type | Tie-bar |
| Number of Poles | 1 |
| Part Number | 493B |
| UPC | 071649229725 |
| Unit Count | 1.0 Count |
| Voltage | 240 Volts |
J**C
Good for the price
Works perfectly well for my application. Should make me compliant with safety rules.
A**Z
So Simple And Effective
I bought this breaker lock-out as a reminder to not turn this breaker on, unless you really need it. I use this on the 240V, 50 AMP, Electric Vehicle / Recreational Vehicle outlet that I installed under our breaker panel. Most of the time, this should be turned OFF, but on rare occassion it needs to be turned on. This Lock-out makes it really easy to remember to keep it turned Off when not needed and prevents people from turning it on by accident. The quality of construction is excellent and although I didn't need to use the fitment accessories that came with it, I appreciate that they were included. Nothing is as frustrating as not being able to finish a project beause of a fitment issue. Master Lock had this in mind and they have you covered. Great little product. I would definately buy it again.
C**Y
Works to cover unused breaker
Works on regular fuse panel
C**R
Not for 4-pole breakers with pairing braces
I bought this lockout for a four pole quadplex breaker. I wanted to shut off the inner toggles of a 240 volt, 40 amp breaker (see pictures). Because the outer metal pairing brace (AKA "that metal thingy"), the lock wouldn't engage with the inner two 40 amp toggles. The description does mention working with tie-bars such as what I have with the 40 amp toggles but when the outer metal pairing brace also exists, this lockout won't work. I've included some pictures that illustrate the problem. Dare I say better pictures than the seller provided. Although this device won't work for me, it seems to be a decent product. I am able to lock out single pole toggles ok. The grip of the toggle is pretty strong. Tighten with the thumbscrew. Then when you swing down the arm, it increases the pressure and it would take some work to pull it off. It might not be suitable to lock out a breaker from a neighbor stealing power but in a safety situation it should be fine. I'm going to keep this lockout for other breakers. I dropped a star mainly because the description is ambiguous, not because the device is poor.
J**3
Simple Solution
Simple circuit lock. Easy to use. It does inhibit me from closing box cover due to height when it's attached to breaker but that is no fault of the product. Very happy with purchase.
C**M
Exactly the same
Perfect. Not cheap plastic. It’s exactly as it should be. And it saves you $15 compared to the warehouse prices
D**K
Best for small breakers
Simple to use and reliable. Turn to knob until the pads touch both sides of the breaker, close the cover and it clamps down. Simply, easy, reliable.
R**B
Works on Residential Breakers
Works on residential breakers. Make sure you use the included bands to make sure the device has enough surface friction to grip. Great for locking out a breaker that leads outside during a project
E**.
Muy buen producto para el trabajo
E**A
Me parece de buena calidad y robusto. un poco caro pero contento con la compra
H**F
Commande reçu à temps et quantité exact contrairement à d’autre. Top top
P**E
Good breaker lock like the snug fit
I**Z
Excelente producto