Are you looking for more information about the Bulgarian key? Do you want to know how burglars open locks, what a Bulgarian pick looks like and which are the best remedies?

Has someone mentioned an anti-Bulgarian-key kit or other solutions to you?

Well, you have landed on the right article.

I am Mauro Semonella, owner of Ariete Security Doors and an armoured door expert (with over 25 years of experience), and in this article you will discover everything there is to know about this tool.

We will talk about latest-generation locks, about remedies and about anti-Bulgarian-key kits.

Ready? Let’s begin!

What the Bulgarian key is, how it works and how to protect yourself

The security of our homes is a need of primary importance.

For many years now, the number of home break-ins has risen considerably, not only in large cities but also in smaller towns.

Intrusions happen especially in detached houses and private homes, but they also affect residents of flats in blocks of flats.

Without raising needless alarm, then, let’s think seriously and sensibly about protecting our safety and that of our loved ones.

We could start by getting to know the break-in techniques used by criminals, so that we are well aware of the risks we may be exposed to.

But what is a break-in?

A break-in is the forcing of a closing mechanism, for example a lock, and it can be carried out with different forced-entry techniques and various tools of all kinds.

Among these, a particularly insidious tool is the so-called Bulgarian key.

The Bulgarian pick: what is it?

The Bulgarian pick is said to have been the method used during the Cold War by Bulgarian spies to slip unseen into the homes of their enemies: hence the origin of the name.

This tool does indeed make it possible to get into homes without any forced entry, because it manages to open doors by duplicating the original key.

Since there has been no break-in in technical terms, the doors and frames are left intact, and the victims of these thefts are not compensated by their insurance companies.

Insult added to injury.

The Bulgarian pick is often, but wrongly, described as an infallible tool for forcing every type of lock.

That is not correct: the Bulgarian key is effective against first-generation double-bit locks operated by long-stem keys.

With this type of lock, the Bulgarian pick manages to slide in easily because it replicates the exact cut of the shaped levers, which are then aligned into the correct position, freeing the locking pin (the so-called “mentonnet“): in this way the key turns and the deadbolts come out.

The Bulgarian key is therefore extremely dangerous because it can reconstruct the profile of a lock’s key without necessarily having the original to hand.

But let’s look in more detail at how all of this happens.

How do burglars open armoured doors with Bulgarian keys?

So, how does this Bulgarian key actually work? you might ask.

First of all, let’s try to understand how it is made, starting from its structure: above all, it can be made up of two parts or of a single piece; in the first case, the components are a “tensioner”, onto which the shape of the lock is copied, and a “soft” key that reads its codes.

With the help of a lathe, it is possible to obtain a virtually perfect duplicate of the original key, even by inserting tiny cameras into the lock to allow still greater precision when the copy is later made.

In the second case, the Bulgarian pick is made up of a single tool that performs both functions, the so-called “magic key“.

In both cases, however, the mechanism is the same:

1. the tensioner puts the lock’s carriage under tension (just as normally happens when the key is turned);
2. the soft key is inserted;
3. by gently shaking the tensioner and the soft key, the vibrations move the teeth of the latter until it takes on the profile matching that of the teeth of the original key.

In this way the profile of one half of the double-bit key is obtained; to produce the other, it is enough to repeat the operation for the second part of the profile.

At this point, the criminal has reproduced a complete double-bit profile, able to open the lock exactly like the original key: without any forced entry, and above all without leaving any trace.

The burglar could even lock the door again with complete peace of mind.

Video by Esperto Antifurti

Bulgarian key: where to buy one?

Buying a Bulgarian key is genuinely easy; you can find it for sale in shops and shopping centres, at prices ranging, depending on the complexity of the gadget, from a minimum of around €20 to a maximum of about €300.

The web is no different: the internet even puts customer reviews at users’ disposal to explain the quality of the product, helping to work out whether the seller is professional and to spot any scams.

We are faced with the most exasperating absurdity: warnings about the possible scam of a tool whose very purpose is to commit a crime!

Online you can even find step-by-step tutorials and very precise instructions on how to make the perfect DIY Bulgarian key yourself.

Given how easy it is to come by, then, let’s try to understand how we can protect ourselves from attacks by the Bulgarian pick.

The Bulgarian key: how to protect yourself?

Anti-Bulgarian-key kit

There are genuine anti-Bulgarian-key kits on the market, at an approximate cost ranging from a minimum of €50 to a maximum of €200; they are advertised as suitable for blocking locks and preventing the use of the pick.

Cerbero lock device

Another remedy is an electro-mechanical device called “Cerbero anti-Bulgarian-key“, described as able to protect any type of lock. The Cerbero lock blocker is operated by a remote control that sends an impulse to the pistons, stopping them from moving: in that situation, not even the owner would be able to get in.

Anti-Bulgarian-key lock

Another option, perhaps the most obvious, is then to install an alarm system with a CCTV camera, which can also be managed remotely.

But the most effective way to defend yourself against the Bulgarian tool is undoubtedly to fit latest-generation anti-Bulgarian-key locks, with flat, coded keys and a euro cylinder.

To find your way through the types, models and prices of the right lock, read our complete guide to the armoured door lock: you will find the differences between the double-bit lock and the euro cylinder, 2026 replacement prices and the leading brands.

The cylinder lock is the one that features, as the name suggests, the cylinder, the true beating “heart” of the lock itself, which makes it far more secure than the double-bit lock for three main reasons:

1. it has narrower slots that hinder the insertion of break-in tools;
2. it guarantees more solidity and resistance thanks to anti-pull and anti-drill reinforcements;
3. it makes key duplication harder, as copies can only be obtained through specialist centres.

As a general rule, let’s say it would be wise to start considering the option of converting the lock if it is old, if the key pattern is very common, or if we do not have a euro cylinder.

Conclusions

To conclude, for the sake of our own peace of mind, let’s think about whether to buy or change the armoured door of our home for one with a lock that can guarantee us security and durability.

We have seen that the Bulgarian pick is one of the most dangerous and also one of the most widespread break-in tools, given how easily it can be found, bought and even built.

The market offers a very wide choice of brands and models of excellent locks able to meet our every need, and to help us defeat that most feared of picks!

The only useful piece of advice is to always turn to serious, reliable companies, represented by people who have the right level of expertise.

Among these, the most innovative have experiential showrooms designed to let customers and designers “get hands-on” with their products: these are not shops in the traditional sense of the word, but “Studios” inside buildings, conceived precisely to offer the chance to try things out before any purchase.

The chance to test the lock mechanisms of the armoured doors on offer for ourselves can help us better understand the break-in techniques used by criminals, who, in this way, might perhaps frighten us a little less.

For more information, come and see us at one of our specialist centres in Genoa, Milan, Monza or Naples, or, request a free quote.

Warm regards,
Mauro