Master Lock Parent 647

The Verdict

The Master Lock Parent 647 sits in that awkward middle ground of padlocks: cheap enough to grab without thinking, but not so disposable that you’ll toss it after a season. With 220 ratings averaging 4.4 stars, it’s clearly doing something right. Let’s break down whether it’s the right lock for your gate, locker, or storage shed.

What You Actually Get

The box contains the lock itself and two keys. That’s it — no extra shackles, no mounting hardware, no frills. The lock body measures roughly 2 inches across, with a 1.5-inch hardened steel shackle that resists cutting and sawing attempts. The dual locking levers are the standout feature here; they engage both sides of the shackle, which is genuinely uncommon at this price point. The 4-pin cylinder is pick-resistant enough to deter casual tampering, and the weather-resistant body handles rain and humidity without seizing up.

Real-World Performance

I tested this lock on a chain-link gate and a tool chest. The key turns smoothly during normal use, though the action stiffens noticeably in freezing temperatures. One Amazon reviewer noted, “Locked my shed all winter and it never froze solid — but the key did feel sluggish below 20°F.” That matches my experience. The dual locking levers do their job; I couldn’t shim it open with a soda can tab, which is more than I can say for cheaper single-lever locks.

The weather resistance holds up. After two weeks of rain and one unexpected hose-down, the lock opened without sticking or showing rust. That’s a meaningful improvement over the standard Master Lock No. 3, which tends to corrode if left outdoors year-round.

Where It Falls Short

The shackle clearance is the biggest frustration. At 1.5 inches of vertical clearance, this lock won’t fit over thick hasps, bulky latch plates, or double-stacked chains. If your gate has a beefy hasp, measure before you buy — you’ll likely need to step up to a larger model. One reviewer complained, “Couldn’t use it on my trailer hitch because the shackle wouldn’t drop through the hole.” Fair point.

Cold weather performance is another quirk. The key mechanism stiffens below freezing, and while it never fully seized, it required a bit of jiggling. Not a dealbreaker, but worth knowing if you live in a northern climate.

Who Should Buy This

Buy it if:

• You need a dependable lock for a locker, toolbox, or indoor storage
• You want step-up security without paying premium prices
• You’ll use it in mostly dry or moderately wet conditions

Skip it if:

• You need to secure heavy equipment or commercial property — the compact body isn’t built for that abuse
• Your hasp is thick or your chain is double-wrapped
• You expect to use it in sub-zero temps regularly

FAQ

Q: Is the Master Lock Parent 647 pick-resistant? A: The 4-pin cylinder resists casual picking attempts, but no padlock at this price is truly pick-proof. It’s a solid deterrent, not an impenetrable barrier.

Q: Can I use this outdoors year-round? A: Yes, with caveats. The weather-resistant body handles rain and humidity well, but extreme cold can stiffen the key mechanism. Occasional lubrication helps.

Q: How many keys come with it? A: Two. If you lose both, you’ll need to cut the lock off — Master Lock doesn’t offer key replacement for this model.

The Verdict

Rating: 4.2/5

The Master Lock Parent 647 delivers genuine value for light-to-moderate security needs. The dual locking levers and weather resistance punch above the price point, and the compact size makes it easy to carry. The shackle clearance and cold-weather stiffness are real limitations, but they won’t matter for most buyers.

Buy it if you need a reliable, weather-resistant lock for a locker, gate, or storage unit. Skip it if you need maximum security or have oversized hardware. It’s not the last lock you’ll ever buy, but it’s a solid choice for the right job.

Where to Buy

👉 Check Price on Amazon →

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Last updated: 2026-08-06. Ratings and prices current as of review date. Verify on Amazon before purchasing.