GREAT SOUTHERN LOCKHigh security
Mul-T-Lock restricted key systems, Melbourne
High-security cylinders and patented keys that can’t be copied at a shopping-centre kiosk. Supplied, installed and managed for homes and businesses across Melbourne’s inner south-east.
- Open 24 hours
- We come to you
- Public liability insured
- ABN registered
- 24/7Answered every hour
of every day - Fully mobileThe workshop comes
to your door - 29 suburbsMelbourne inner
south-east coverage - Insured & ABNPublic liability cover
ABN registered
The problem
An ordinary key is a four-minute problem
An ordinary key is a piece of metal anyone can duplicate in four minutes for a few dollars, with no record and no permission. For most front doors that’s fine. For a building where you need to know exactly who can get in, it’s a real hole.
A restricted system closes it. The blanks are patented and supplied only to authorised locksmiths, and cutting one requires your written authority — so the list of people who can open your door is a list you actually control.
What you gain
Three problems a restricted system ends
Uncontrolled copies
Nobody can duplicate your key at a kiosk on the way home. New keys exist only when you authorise them, so the number in circulation is a number you know.
A register that means something
The system is recorded against you. In three years, when someone asks who holds a key, there is an actual answer rather than a guess.
Harder cylinders, not just harder keys
Mul-T-Lock cylinders are built to resist picking, bumping and drilling — the attacks that make short work of standard hardware.
Where it earns its money
- Businesses with staff turnover — no more uncertainty about old keys.
- Landlords and property managers — controlled access across a portfolio.
- Share houses and student accommodation — where keys multiply quietly.
- Home businesses and clinics — stock, records or equipment on site.
- Anywhere too many keys already exist — a clean reset.
What’s involved
Usually a cylinder swap rather than new door hardware, so it’s a smaller job than most people assume. We work out how many keys you need and who holds them, set the system up, and register it so future keys can only be cut with your say-so.
Not sure you need it? Say so on the phone. Plenty of jobs are better served by a straight rekey, and you’ll be told that rather than sold a system you don’t need.
Good questions to ask
- How many keys do I actually need?
- Who authorises new copies?
- Does my existing door hardware stay?
- What happens if a key is lost?
All fair questions. You'll get straight answers before anything is ordered.
Call 0468 770 558Want to control who holds a key?
Call and describe the building — you'll get an honest read on whether it's worth it.
Read next
Guides on this
Longer answers to the questions that come up before people ring.
Questions
Restricted key questions
What makes a key “restricted”?
The blank is patented and controlled. An ordinary key can be copied at any kiosk in any shopping centre. A restricted key can only be cut by an authorised locksmith, against the written authority of whoever holds the system. That’s the whole point of it.
Is it worth it for a house?
For a lot of houses, no — a good standard deadlock and a rekey does the job. It earns its cost when you genuinely need to control copies: a share house, a rental you manage, a home business, or a property where too many keys have gone walkabout over the years.
Can I still get spare keys cut?
Yes — through us, with your authorisation. You’re not locked out of your own system; you’re just the only one who can authorise additions to it.
Does it replace my whole door?
No. In most cases only the cylinder changes — the existing door hardware stays. It’s a smaller job than people expect.
What if I lose a restricted key?
Ring us. Because copies are controlled, a lost key is a much smaller problem than with an ordinary system — nobody can walk into a kiosk and duplicate it. We can rekey the system if you want the lost key made dead.
Other things we do
Car key replacement
Lost every key to the car? We cut and program a new one at the roadside for most makes and models — no tow, no dealership wait.
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24/7 emergency lockout
Locked out of the house, car or shop. Non-destructive entry wherever it’s possible, any hour of the night.
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Lock rekeying & changes
New place, old tenant, or a key that walked off. Rekeying kills the old keys without paying for all-new hardware.
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Commercial locksmith
Shopfronts, offices and rentals. Master key systems, restricted keys and scheduled maintenance for property managers.
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Deadlocks & window locks
Proper deadbolts on every external door, patio bolts on sliders and key locks on the windows that matter. Keyed alike if you want one key.
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